Indian Journal of Experimental Biology

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VOLUME 50

NUMBER 10

OCTOBER 2012

CODEN: IJEB (A6) 50 (9) 591-664 (2012)

ISSN: 0019-5189 (Print); 0975-1009 (Online)

 

CONTENTS

 

Papers

 

 

 

Generation of HIV-1 based bi-cistronic lentiviral vectors for stable gene expression and live cell imaging

669

 

 

Lalit Sehgal, Srikanth B, Khyati Bhatt, Sneha Sansare, Amitabha Mukhopadhyay, Rajiv D Kalraiya & Sorab N Dalal

 

 

 

Ampicillin alone and in combination with riboflavin modulates Staphylococcus aureus
infection induced septic arthritis in mice

677

 

 

Pinky Mal, Deboshree Ghosh, Debasish Bandyopadhyay, Kallol Dutta & Biswadev Bishayi

 

 

 

Effect of seabuckthorn extract on scopolamine induced cognitive impairment

690

 

 

Dharam Paul Attrey, Amrit Kumar Singh, Tanveer Naved & Balgangadhar Roy

 

 

 

Effects of perinatal exposure of lithium on neuro-behaviour of devoloping mice offspring

696

 

 

Gasem M Abu-Taweel

 

 

 

Abortifacient activity of Plumeria rubra (Linn) pod extract in female albino rats

702

 

 

Dinesh Dabhadkar & Varsha Zade

 

 

 

Effect of Pinus massoniana Lamb. bark extract on lytic cycle of Epstein-Barr virus

708

 

 

Shuxia Xu, Shimin Zhang, Xuedong Wang, Yuqian Gao, Xing Qin & Kun Wu

 

 

 

Antimicrobial activity of some promising plant oils, molecules and formulations

714

 

 

Dwijendra Singh, T R S Kumar , Vivek  K Gupta, & Pushplata Chaturvedi

 

 

 

Screening, isolation, taxonomy and fermentation of an antibiotic producer Streptomyces xinghaiensis from soil capable of acting against linezolid resistant strains

718

 

 

Konda Shravan Kumar, Sriramoju Anuradha, Gadepalli Rama Sarma, Yenamandra Venkateshwarlu & Veerabrahma Kishan

 

 

 

Protocol for augmented shoot organogenesis in selected variety of soybean [Glycine max L. (Merr.)]

729

 

 

M K Akitha Devi, G Sakthivelu, P Giridhar & G A Ravishankar

 

 

 

High acid invertase activity for a prolonged period in developing seeds/podwall of wild chickpea is detrimental to seed filling

735

 

 

Harinderjeet Kaur, Anil Kumar Gupta, Narinder Kaur & Jeet Singh Sandhu

 

 

 

Individual variation in response to simulated hypoxic stress of rats

744

 

 

Dishari Ghosh, Rajesh Kumar & Karan Pal

 

 

 

Announcements

 

 

 

Second National Symposium on Innovative Approaches and Modern Technologies for Crop Productivity, Food Safety and Environmental Sustainability, International Conference on Recent Trends in Climate Change Researches vis-ŕ-vis Biodiversity

668

 

—————————————————

 

Announcements

 

Second National Symposium on Innovative Approaches and Modern Technologies for Crop Productivity, Food Safety and Environmental Sustainability

19-20 November 2012, Thrissur

 

Organised by the Society for Applied Biotechnology, the symposium will be held at the Hotel Mangala Towers, Paliyam Road, Near Vadakke Bus Stand, Thrissur 680 001, Kerala. The major themes are: (i) Modern perspectives in agriculture–approaches, challenges and opportunities, (ii) Crop diversification, sustainable utilization and biodiversity conservation, (iii) Application of biotechnology and nanotechnology to increase agricultural productivity, (iv) Sustainable and eco-friendly approaches for agricultural productivity, (v) Environmental management of degraded ecosystems and reclamation of polluted soils, (vi) Biodegradation and bioaccumulation of oils, heavy metals and other toxic pollutants, (vii) Identification, characterization and preservation of biodiversity through modern techniques, (viii) Food safety, food security and poverty alleviation, (ix) Impacts of global warming and climate change on agriculture and environment, and (x) Impact of genetically modified organisms and other biotechnology products. For further details please contact: Dr. Devarajan Thangadurai, President, Society for Applied Biotechnology, Molecular Breeding Laboratory, Department of Botany, Karnatak University, Dharwad 580 003, Mobile: 0 94826 85270/96559 98280/99860 50133. E-mail: drdthangadurai@gmail.com, drthangaduraid@gmail.com, thanga@sabt.org.in

 

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International Conference on Recent Trends in Climate Change Researches vis-ŕ-vis Biodiversity

3-4 December 2012, M J P Rohilkhand University, Bareilly

Organised under the auspices of Centre of Excellence sanctioned by the Government of Uttar Pradesh, by the Department of Animal Science, in collaboration with The Indian Academy of Environmental Sciences, the conference will cover following topics under Environmental and climate changes and their impact on (a) Biodiversity and ecology, (b) Fisheries and Aquaculture, (c) Parasitic diseases and epidemiology, (d) Insect and vector biology, (e) Molecular biology and immunology, and (f) Biomedicine and biotechnology. For details, please contact: Prof. Neelima Gupta, Department of Animal Science, MJP Rohilkhand University, Bareilly 243 006, India. Telephone: 0581-2520888 (O); 2544116, 2548686 (R) Mobile: +91-9412376677. E-mail: guptaby@gmail.com, guptagrawal@rediffmail.com

 

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Author Index

Abu-Taweel Gasem M

696

Anuradha Sriramoju

718

Attrey Dharam Paul

690

 

 

B Srikanth

669

Bandyopadhyay Debasish

677

Bhatt Khyati

669

Biswadev Bishayi

677

 

 

Chaturvedi Pushplata

714

 

 

Dabhadkar Dinesh

702

Dalal Sorab N

669

Devi M K Akitha

729

Dutta Kallol

677

 

 

Gao Yuqian

708

Ghosh Deboshree

677

Ghosh Dishari

744

Giridhar P

729

Gupta Anil Kumar

735

Gupta Vivek  K

714

 

 

Kalraiya Rajiv D

669

Karan Pal

744

Kaur Harinderjeet

735

Kaur Narinder

735

Kishan Veerabrahma

718

Kumar Konda Shravan

718

Kumar T R S

714

 

 

Mal Pinky

677

Mukhopadhyay Amitabha

669

 

 

Naved Tanveer

690

 

 

Qin Xing

708

 

 

Rajesh Kumar

744

Ravishankar G A

729

Roy Balgangadhar

690

 

 

Sakthivelu G

729

Sandhu Jeet Singh

735

Sansare Sneha

669

Sarma Gadepalli Rama

718

Sehgal Lalit

669

Singh Amrit Kumar

690

Singh Dwijendra

714

 

 

Wang Xuedong

708

Wu Kun

708

 

 

Xu Shuxia

708

 

 

Yenamandra Venkateshwarlu

718

 

 

Zade Varsha

702

Zhang Shimin

708

 

 

Keyword Index

Abortifacient

702

AChE activity

690

ACTH

744

Ampicillin

677

Antibiotic

718

Antimicrobial

714

Antioxidant enzymes

677

 

 

Bark extract

708

Behaviour

696

Bi-cistronic lentiviral vector

669

 

 

Carbohydrate

735

Catecholamine

744

CBG

744

Cognitive impairment

690

Corticosterone

744

Cotyledonary node

729

Cytokines

677

 

 

EA-D

708

Epstein-Barrr virus

708

Essential oil

714

Esterases

696

 

 

Female albino rat

702

Fluorescent tag

669

FRET

669

Geraniol

714

Glycine max

729

 

 

HIV-I

669

Hypoxic stress

744

 

 

In vitro rooting

729

In vivo imaging

669

Inflammation

677

Invertase

735

 

 

Linezolid resistance

718

Lithium

696

Locomotor activity test

696

Lytic cycle

708

 

 

Mice offspring

696

Microshoots

729

Multiple cloning site

669

 

 

PEP carboxylase

735

Perinatal exposure

696

Pinus massoniana

708

Plant product

714

Plumeria rubra

702

Post implantation

702

Reactive oxygen species

677

Reductiomycin

718

Resorption

702

Riboflavin

677

Rta

708

 

 

S. aureus

677

Scopolamine

690

Seabuckthorn leaf extract

690

Seed-filling

735

Sensory motor reflexes

696

Septic arthritis

677

Shoot buds

729

Stable transgene expression

669

Streptomyces xinghaiensis

718

Sucrose synthase

735

Synovial inflammation

677

 

 

Testosterone

744

Toxic shock syndrome toxin


677

Triacontanol

729

 

 

Wild Cicer species

735

 

 

Zta

708

 

 

 

 

 

Correspondent author has been indicated by * sign

 

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 669-676

 

 

Generation of HIV-1 based bi-cistronic lentiviral vectors for
stable gene expression and live cell imaging.

Lalit Sehgal#, Srikanth Budnar#, Khyati Bhatt, Sneha Sansare, Amitabha Mukhopadhaya,
Rajiv D Kalraiya & Sorab N Dalal*

KS215, Advanced Centre for Treatment Research & Education in Cancer, (ACTREC), Tata Memorial Centre,
Kharghar Node, Navi Mumbai 410 210, India

Received 13 April 2012; revised 25 July 2012

The study of protein-protein interactions, protein localization, protein organization into higher order structures and organelle dynamics in live cells, has greatly enhanced the understanding of various cellular processes. Live cell imaging experiments employ plasmid or viral vectors to express the protein/proteins of interest fused to a fluorescent protein. Unlike plasmid vectors, lentiviral vectors can be introduced into both dividing and non dividing cells, can be pseudotyped to infect a broad or narrow range of cells, and can be used to generate transgenic animals. However, the currently available lentiviral vectors are limited by the choice of fluorescent protein tag, choice of restriction enzyme sites in the Multiple Cloning Sites (MCS) and promoter choice for gene expression. In this report, HIV-1 based bi-cistronic lentiviral vectors have been generated that drive the expression of multiple fluorescent tags (EGFP, mCherry, ECFP, EYFP and dsRed), using two different promoters. The presence of a unique MCS with multiple restriction sites allows the generation of fusion proteins with the fluorescent tag of choice, allowing analysis of multiple fusion proteins in live cell imaging experiments. These novel lentiviral vectors are improved delivery vehicles for gene transfer applications and are important tools for live cell imaging in vivo.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 677-689

 

 

Ampicillin alone and in combination with riboflavin modulates Staphylococcus aureus infection induced septic arthritis in mice

 

Pinky Mala, Deboshree Ghoshb, Debasish Bandyopadhyayb Kallol Duttaa† & Biswadev Bishayia*

Department of Physiology, a Immunology laboratory, b Oxidative Stress and Free Radical Biology Laboratory,University Colleges of Science and Technology, University of Calcutta, 92 APC Road, Kolkata 700 009, India

Received 21 November 2011; 20 July 2012

Effects of ampicillin (Amp) in combination with riboflavin on septic arthritis in mice infected with Staphylococcus aureus have been reported. Ampicillin was given at 100 mg/kg after 24 h of infection, followed by riboflavin (Ribo) at 20 mg/kg body wt, after 2 h of Amp treatment. Mice were sacrificed at 3, 9, 15 days post infection (dpi). Combined treatment of infected mice with ampicillin and riboflavin eradicated the bacteria from blood, spleen and synovial tissue and showed a significant gross reduction in arthritis, reduced serum levels of TNF-α and IFN-γ. S. aureus infected mice exhibited higher synovial TNF-α and IL-6, which was also reduced by ampicillin and riboflavin treatment. S. aureus infected mice showed a disturbed antioxidant status measured in terms of cellular anti-oxidants like reduced glutathione and anti-oxidant enzymes such as superoxide dismutase and catalase and were ameliorated when the animals were co-treated with ampicillin along with riboflavin. Results of the study showed that combined treatment with anti-oxidant and antibiotic may protect from staphylococcal arthritis and may ameliorate oxidative stress caused by S. aureus infection.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 690-695

 

 

Effect of seabuckthorn extract on scopolamine induced cognitive impairment

Dharam Paul Attrey1*, Amrit Kumar Singh1, Tanveer Naved2 & Balgangadhar Roy3

1Amity Institute of Seabuckthorn Research, 2Amity Institute of Pharmacy,

Amity University Uttar Pradesh, Sector 125, NOIDA 201 303, India

3Institute of Nuclear Medicine & Allied Sciences (INMAS), DRDO, Timarpur, Delhi 110 054, India

Received 18 April 2012; revised 30 July 2012

Present study involves evaluation of effects of 75% ethanolic extract of seabuckthorn [Hippophae rhamnoides L. (SBT)] leaves on scopolamine induced cognitive impairment in rats using three different oral doses i.e. 50, 100 and 200 mg/kg body weight through assessment of various biochemical and behavioural parameters. Scopolamine administration resulted in an increase in acetylcholinesterase (AChE) activity (approximately 9% with respect to the control group) and malonaldehyde (MDA) content. The increased AChE activity was significantly reduced in animals receiving 200 and 100 mg/kg of SBT extract. Animals treated with SBT extract showed significantly reduced MDA level in all the doses. This reduction in MDA content indicates that SBT leaf extract has potent antioxidant activities and exhibits a protective effect against oxidative damage induced by scopolamine. Behavioural studies also indicated significant improvement. The results suggest that SBT leaf extract has potential effects against scopolamine induced cognitive impairment by regulating cholinergic marker enzyme activity (AChE activity) and promoting the antioxidant system and may be explored for its use in cognitive disorders.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 696-701

 

 

Effects of perinatal exposure of lithium on neuro-behaviour of developing
mice offspring

Gasem M Abu-Taweel

Department of Biology, College of Education, Dammam University, P.O. Box 2375, Dammam 31451, Saudi Arabia

Received 4 April 2012; revised 12 July 2012

Lithium (Li) was given to female Swiss-Webster strain mice at the doses of 15 and 30 mg/kg body weight in their drinking water. Treatment started from the first day of pregnancy until the postnatal day fifteen of delivery. Thereafter, the dams were switched to plain tap water. All offspring were subjected to various tests. The rate of body weight gain was relatively slower in Li exposed pups. Furthermore, the opening of eyes and appearance of body hairs in Li exposed pups were also slower as compared to the controls. The sensory motor reflexes in Li exposed pups were found to be affected in a dose-dependent manner. Significant relative changes were also noticed in the levels of acid and alkaline phosphatases in the liver, and acetylcholinesterase in the brain tissues of the Li exposed developing offspring in a dose-dependent manner. ‘Locomotor Activity Test’ was performed in the male offspring only which showed a significant suppressive effect on most of the elements of this test due to Li exposure. The present Li effects in the offspring are possibly via in utero action and/or via mother’s milk.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 702-707

 

 

Abortifacient activity of Plumeria rubra (Linn) pod extract in female albino rats

Dinesh Dabhadkar & Varsha Zade*

Department of Zoology, Government Vidarbha Institute of Science and Humanities, Amravati 444 604, India

Received 21 March 2012; revised 23 July 2012

To evaluate the potential abortifacient activity of the aqueous, alcohol, ethyl acetate and chloroform extracts of P. rubra pod in female albino rats 50, 100 and 200 mg/kg body weight doses of each extract were administered from day 11 to 15 of pregnancy and animals were allowed to go full term. The phytochemical screening revealed the presence of alkaloids, flavonoids, simple phenolics, steroids, tannins and saponins. Clinical toxicity symptoms such as respiratory distress, salivation, weight loss, dull eyes, diarrhea, and change in the appearance of fur as well as mortality were not observed in the animals at any period of the experiment. All the four extracts of P. rubra pods exhibited abortifacient activity (8-100%). The extracts significantly reduced the number of live fetuses, whereas the resorption index and post implantation losses increased significantly. The % of abortion was found to be highest (100%) with 200 mg/kg dose of alcoholic extract of P. rubra pods.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 708-713

 

 

Effect of Pinus massoniana Lamb. bark extract on lytic cycle of Epstein-Barr virus

Shuxia Xu1, Shimin Zhang1*, Xuedong Wang2, Yuqian Gao1, Xing Qin & Kun Wu1*

1College of Life Science, Henan Agriculture University, Zhenzhou, Henan, China

2School of Environmental Science and Public Health, Wenzhou Medical College, Wenzhou, China

Received 16 March 2012; revised 30 July 2012

Pinus massoniana bark extract (PMBE) at a concentration of 60 μg/mL or more inhibits the expression of Epstein–Barr virus (EBV) lytic proteins, such as Rta, Zta, and EA-D. EBV lytic cycle was blocked by inhibiting the transcription of immediate-early genes. The results suggest that the PMBE has anti-EBV activity. Thus, the extract is potentially useful in preventing the lytic development of EBV in vitro.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 714-717

 

 

Antimicrobial activity of some promising plant oils, molecules and formulations

Dwijendra Singh1*, T R S Kumar2,†, Vivek K Gupta2,**, & Pushplata Chaturvedi2

1Microbial Technology and Entomology Department, Crop Protection Division, 2Genetic Resources and Biotechnology Division,
CSIR-Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow 226 016, India

Received 4 September 2011; revised 30 July 2012

Plant oils and oil components were screened in vitro for antibacterial and antifungal activity by disc diffusion method. Minimum Inhibitory Concentrations (MICs) of oils (% v/v) against bacteria and fungi were determined by agar dilution method. Results showed that potential antimicrobial activity was demonstrated by geranium oil, geraniol, and terpineol. These oils and oil components were active against Gram-positive and Gram-negative bacteria pathogens. Antifungal activity was also observed against dermatophytes, yeasts and Aspergillus species. Antimicrobial formulations containing geranium oil, geraniol and terpineol showed strong antibacterial and antifungal activity.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 718-728

 

 

Screening, isolation, taxonomy and fermentation of an antibiotic producer Streptomyces xinghaiensis from soil capable of acting against
linezolid resistant strains

Konda Shravan Kumar1, Sriramoju Anuradha1, Gadepalli Rama Sarma2, Yenamandra Venkateshwarlu3
& Veerabrahma Kishan1,*

1University College of Pharmaceutical Sciences, Kakatiya University, Warangal 506 009, India

2Department of Medicinal Chemistry, School of Pharmacy, University of Mississippi, USA

3Natural Product Laboratories, Organic Chemistry Division -1, CSIR-Indian Institute of Chemical Technology, (CSIR-IICT),
Hyderabad 500 007, India

Received 14 November 2011; revised 11 July 2012

Linezolid resistant cultures are emerging in hospitals. In the present study 3 soil actinomycetes were isolated in a screening programme having potential to produce antibiotic against linezolid resistant cases. One culture was coded as RK-46 and further studied. The micromorphology, biochemical tests and 16S ribosomal DNA gene sequence analysis were conducted to know the identity of the culture and was found as a strain of Streptomyces xinghaiensis. The culture produced antibiotic active against five clinical resistant strains. The antibiotic production was tested by cultivating in eleven different media. The fermentation profile was studied in YEME medium supplemented with calcium carbonate. The maximum activity was noticed at 72 h. Antibiotic activity was extracted into ethyl acetate and was subjected to activity guided purification by column chromatography, TLC and HPLC methods. The pure compound was eluted with retention time of 6.8 min and subjected to 1H, 13C NMR and Mass spectral analysis. The acquired data was compared with that in natural products data base, and was found to be a known antibiotic, reductiomycin. The purified compound showed activity against 5 linezolid resistant cultures and on Mycobacterium tuberculosis. This compound is also showing mild anti cancer activity and is biologically permeable as per Lipinksi’s rule.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 729-734

 

 

Protocol for augmented shoot organogenesis in selected variety of soybean [Glycine max L. (Merr.)]

M K Akitha Devi, G Sakthivelu, P Giridhar* & G A Ravishankar

Plant Cell Biotechnology Department,
CSIR-Central Food Technological Research Institute (CFTRI), Mysore 570 020, India

Received 16 December 2011; revised 27 July 2012

Development of a reproducible, versatile and efficient in vitro plant regeneration system is highly warranted for Indian soybean varieties for their mass multiplication in view of their commercial significance. Accordingly a protocol for direct shoot organogenesis in soybean variety JS 335 has been developed. Using cotyledonary node explants significant organogenic responses, mean shoot number and shoot length were observed when these were incubated on MS medium supplemented with 0.89 µM Benzyladenine (BA) and 5 μg/L triacontanol (TRIA) where in 9.3 ± 0.5 shoots were obtained. TRIA at 5 μg /L able to produce 6.8 ± 0.5 shoot buds in presence of 0.98 µM IBA and 0.89 µM BA. Highest mean shoot buds (14.0 ± 0.5 and 9.0 ± 0.5) and mean shoot length (4.6 ± 0.3 and 10.0 ± 0.7) were obtained when cotyledonary node and shoot tip explants were cultured on MS medium containing 0.14 µM gibberellic acid (GA3), 0.89 µM BA and 5 μg/L TRIA. Moreover, TRIA supported highest mean root number (6.3±0.5) and root length (21.5 ± 0.57 cm). Field survival of in vitro derived plants of TRIA treatment was 70% and the overall growth and seed yield was also significantly better than control plants. This protocol may be used for improving the in vitro regeneration of soybean variety JS 335 for transformation studies.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 735-743

 

 

High acid invertase activity for a prolonged period in developing
seeds/podwall of wild chickpea is detrimental to seed filling

Harinderjeet Kaur1, Anil Kumar Gupta1*, Narinder Kaur1 & Jeet Singh Sandhu2

1Department of Biochemistry and 2Department of Plant Breeding & Genetics,
Punjab Agricultural University, Ludhiana 141 004, India

Received 24 January 2012; revised 26 July 2012

In the present study factors responsible for low seed biomass in wild Cicer species has been investigated. Cicer judaicum and chickpea cultivar PBG-1 were investigated to compare activities of some enzymes involved in carbon metabolism in podwall and seeds during crop development. Seed filling duration in wild species was about 15 days shorter than that of cultivated varieties due to rapid loss of moisture content and hence resulted in earlier maturity and reduced seed biomass. Longer seed filling duration appeared to be an important factor responsible for greater biomass of chickpea seeds. Because of absence of phosphoenol pyruvate carboxylase from 25-35 days after flowering and low sucrose synthase activities, the podwall of C. judaicum is not in a position to contribute significantly to the sink filling capacity of seeds. High acid invertase, low sucrose synthase activities during seed storage phase cause detrimental effect on seed filling and resulting in highly reduced sink strength and productivity of wild species. Successful transfer of stress tolerance from wild Cicer species to chickpea cultivars need to prevent the transfer of these observed unfavourable biochemical factors so that the productivity of chickpea crop remains unaffected during utilization of wild Cicer species in chickpea improvement.

 

 

Indian Journal of Experimental Biology

Vol. 50, October 2012, pp. 744-748

 

 

Individual variation in response to simulated hypoxic stress of rats

Dishari Ghosh*, Rajesh Kumar & Karan Pal

Endocrinology and Metabolism Laboratory, Defence Institute of Physiology and Allied Sciences

Defence Research and Development Organization, Lucknow Road, Timarpur, Delhi 110 054, India

Received 4 January 2012; revised 29 June 2012

With an aim to categorize the animals exposed to simulated hypobaric hypoxia and to evaluate the hormonal profile responsible for individual variation in response to hypoxic stress, degree of tolerance to hypobaric hypoxia was measured by exposing the animals to a simulated altitude of 10,668 m at 32 °C and animals were categorized as low and high tolerant groups based on their gasping time. The hormonal profiles of these groups were evaluated just after exposure to the test. The results showed a distinct individual difference in response to hypoxic tolerance test. There was a significant increase in plasma norepinephrine concentration in high tolerant group than low tolerant rats. After hypoxic tolerance test, total circulating corticosterone (CORT) level also increased but this was not significant in high tolerant rats as compared to low tolerant rats. Corticosteroid binding globulin (CBG) concentration differ significantly between high and low tolerant groups of rats resulting in significant changes in circulating free corticosterone that in turn may be responsible for individual differences in hypoxic gasping time. Significant differences were also observed in prolactin and testosterone levels of both the groups. The results established the method of differentiating the animals according their response to hypoxic tolerance test. These data indicate that multiple components rather than only plasma glucocorticoid of the stress response are providing a basis for individual differences in physiological responses to hypoxic stress.