title: Age dependent expression of melatonin membrane receptor (MT1, MT2) and its role in regulation of nitrosative stress in tropical rodent Funambulus pennanti.
abstract: Age-dependent declining level of melatonin induces free radical load and thereby deteriorates immune function. However, reports are lacking about age-dependent melatonin membrane receptor (MT1 & MT2) expression, their role in regulation of reactive nitrogen species (RNS) and eventually how they affect immunity of a tropical rodent F. pennanti. We checked MT1R, MT2R and iNOS expression in lymphoid organs of young middle and old aged squirrels. Nitrite and nitrate ion concentration (NOx) in lymphoid organs, testes and plasma, lymphocyte proliferation and IL-2 level was recorded. Age-dependent decrease in MT1 and MT2 receptor expression, lymphocyte proliferation, IL-2 level and increased RNS in lymphoid organs, testes and plasma was observed with decreased circulatory melatonin. Androgen and AR expression was increased in middle-aged while declined in old-aged squirrels. Present study suggests that age associated immunosenescence is consequence of increased RNS which might have important relationship with melatonin membrane receptors in F. pennanti.
authors.affiliation: Department of Zoology, Banaras Hindu University, Varanasi, India.
authors.forename: Raise
authors.initials: R
authors.lastname: Ahmad
authors.forename: Sameer
authors.initials: S
authors.lastname: Gupta
authors.forename: Chandana
authors.initials: C
authors.lastname: Haldar
mesh_terms: D000367:Age Factors; D000818:Animals; D049109:Cell Proliferation; D002478:Cells, Cultured; D015870:Gene Expression; D005786:Gene Expression Regulation; D007376:Interleukin-2 / Q000097:blood / Q000378:metabolism; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000378:metabolism / Q000502:physiology; D008297:Male; D008550:Melatonin / Q000097:blood / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D026361:Reactive Nitrogen Species / Q000097:blood / Q000378:metabolism*; D044122:Receptor, Melatonin, MT1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D044123:Receptor, Melatonin, MT2 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D011944:Receptors, Androgen / Q000378:metabolism; D012589:Sciuridae / Q000378:metabolism / Q000502:physiology*; D013154:Spleen / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D013312:Stress, Physiological; D013737:Testis / Q000201:enzymology / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D013950:Thymus Gland / Q000166:cytology / Q000201:enzymology / Q000378:metabolism
chemical_list: D007376:Interleukin-2; D026361:Reactive Nitrogen Species; D044122:Receptor, Melatonin, MT1; D044123:Receptor, Melatonin, MT2; D011944:Receptors, Androgen; D013739:Testosterone; D052247:Nitric Oxide Synthase Type II; D008550:Melatonin