The rat thymus--a site of atrial natriuretic peptide synthesis.
The atrium of the heart has been demonstrated to represent the major site of synthesis of atrial natriuretic peptide (ANP), a potent natriuretic, diuretic and vasoactive hormone. Our recent studies revealed ANP-like material outside the heart, namely, in lymphoid follicles of the intestine and in the thymus, and now we report data demonstrating the thymus as a site of synthesis for ANP. The experimental evidence is as follows: firstly, the immunoreactive material detected corresponds chromatographically with the precursor of ANP. Secondly, the thymus contains mRNA for ANP. Thirdly, immunohistochemistry locates ANP-like material to cortical thymocytes with particularly dense staining in the subcapsular areas of the thymus. Interestingly, both ANP-like material and the mRNA coding for ANP were expressed to a larger extent in newborn rats as compared to adult animals, suggesting that ANP may be involved in the development and/or function of T-cells.
Vollmar
A M
AM
Institute of Pharmacology, Toxicology and Pharmacy, University of Munich, München, FRG.
Lang
R E
RE
Hänze
J
J
Schulz
R
R
D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism; D009320:Atrial Natriuretic Factor / Q000096:biosynthesis* / Q000235:genetics; D015152:Blotting, Northern; D007124:Immunoenzyme Techniques; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013950:Thymus Gland / Q000378:metabolism*
D012333:RNA, Messenger; D009320:Atrial Natriuretic Factor