Diapedesis of thrombocytes from capillary into the intercellular space of interscapular brown adipose tissue and their increase by Ca-Sandoz.
Diapedetic capacity of the rat thrombocytes to leave capillaries of the interscapular brown adipose tissue (IBAT) and infiltrate the interstitium has been observed by conventional electron-microscopy. Thrombocytes that reach IBAT interstitium are morphologically completely different from lumenary ones. The interstitial thrombocyte has a prominet head region (1.51 x 2.12 microns) and very long phylopodium (3.43 microns). Experimental conditions which induced drastic changes in morphology of interstitial thrombocytes were: sucrose overfeeding (10% over 2 days); a 24 hour starving after sucrose overfeeding and Ca-Sandoz drinking (480 mg/L Ca2+ during 2 days). The thrombocytes in the IBAT interstitium can be classified as activated according to: a) pseudopode extension; b) swollen open canalicullar system (OCS); c) endocytosis via coated pits and vesicles; and d) structural changes in alpha granules excreted to the interstitium through OCS. In the IBAT interstitium of 24-hour starved rats after sucrose overfeeding, a thrombocytic layer was observed. It was suggested that thrombocyte adrenalin, stored in dense bodies, was selectively included in the IBAT supply without mediation of the central nervous system.
Radovanović
J
J
Institute of Zoology, Faculty of Biology, University of Belgrade, Yugoslavia. jelenar@bf.bio.bg.ac.yu
Korać
A
A
Koko
V
V
Nedeljković
M
M
Drndarević
N
N
D002001:Adipose Tissue, Brown / Q000166:cytology*; D000818:Animals; D001792:Blood Platelets / Q000166:cytology*; D002118:Calcium; D002196:Capillaries / Q000166:cytology*; D002465:Cell Movement; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D007424:Intracellular Fluid; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013395:Sucrose / Q000378:metabolism
D013395:Sucrose; D002118:Calcium