Intestinal absorption of l4C amino acids and its transport in the altered blood balance of Na+ and Ca2+ in malfunction of the parathyroid glands in rats

Abstract

Malfunction of the parathyroid glands (PG) results in impairments ofsome vital processes. Intestinal absorption and tissue transport ofamino acids under this condition are little studied. The present study deals with the transfer of labeled ¹⁴C-amino acidsfrom the intestine to blood and tissue ofparathyroid-malfunctioned rats. In albino male rats weighing 120-140 g, electrocoagulation was used to induce PG malfunction and on days 5-6 after surgery a mixture ofequimolar quantities oflabeled ¹⁴C-aminoacids with a specific radioactivity of240mCu/mM (Czechia) at the rate of50 pCu per lOOgofanimal weight was administered into theirstomaches. The exposure lasted 45 minutes. The radioactivity in the blood and tissues was measured on a SL42221 spectrometer (Roche-Bioelectronic, France). The readings were expressed in impulses/g ofraw tissue per min. The content of Na⁺ and Ca²⁺ was assayed by the ion-selective test on a Microlite analyzer (Kone, Finland) PG malfunction was found to impair the balance of Na⁺ and Ca²⁺ , to increase the transfer oflabeled ¹⁴C-amino acidsfrom the intestine to the blood by 86.4%, thatfrom the blood to the liver, kidney, heart, and spleen by 22.9, 38.1, 55.3, 73.5%, respectively. The observed increase in the concentration oflabeled ¹⁴C-amino acids in the blood and tissues ofparathyroid-malfunctioned rats is likely to be explained by enhancedpassive diffusion and mechanisms that are responsibleforthe transport ofamino acids under the altered balance of Na⁺ and Ca²⁺ w in PG malfunction.