Fj. Martin et al., EFFECT OF STREPTOZOTOCIN-INDUCED DIABETES-MELLITUS ON SEROTONIN MEASURES OF PERIPHERAL-TISSUES RAT, Life sciences, 56(1), 1994, pp. 51-59
Citations number
40
Categorie Soggetti
Biology,"Medicine, Research & Experimental","Pharmacology & Pharmacy
The present study was conducted to examine whether experimental diabet
es (streptozotocin-induced) promotes changes in serotonin (5HT) measur
es of peripheral tissue. Platelet-free plasma 5HT, tryptophan and 5-hy
droxyindolacetic acid (5HIAA), whole blood 5HT and renal, liver, intes
tinal and lung 5HT and 5HIAA levels were measured in rats of four expe
rimental groups: control, diabetic, diabetic+insulin and non-diabeticinsulin. Several serotonin measures were unaltered in all four experim
ental groups, i.e. plasma, liver and lung 5HT and 5HIAA levels. Whole
blood 5HT levels descended about 50% in diabetic rats, then recovered
their proper levels after 1 week of insulin therapy. Diabetic animals
Rad a significantly greater intestinal 5HT concentration (+50% versus
control), while intestinal 5HIAA levels did not achieve statistical si
gnificance despite a -26% decrement in their value. Both renal 5HT and
5HIAA levels were decreased in diabetic animals and recovered with in
sulin therapy. Peripheral tissue 5HT measures were not varied by insul
in administration to non-diabetic animals. The results are consistent
with a 5HT release, which is diminished in enterochromaffin cells and
enhanced in platelet concomitantly to a minor platelet 5HT uptake, for
explaining alterations of plasma/blood 5HT measures in experimental d
iabetes, and with a diminished synthesis of 5HT for explaining renal c
hanges.