Further studies on the effect of glucose concentrations and other oxidizable substrates upon ionic gradients and in vitro somatostatin release from rat mediobasal hypothalamus.
During in vitro incubation of rat mediobasal hypothalamus (MBH), potassium and sodium gradients were high in the presence of glucose, pyruvate, lactate or the mixture glucose and pyruvate; in the absence of substrate, the ionic gradients were markedly lowered and corresponding somatostatin release from MBH was maximal. The specific effect of glucose on somatostatin release from MBH was tested under normal tissue polarization, i.e. in the presence of pyruvate. Under these more physiological conditions, somatostatin release was submaximal and inversely related to glucose concentrations (within the range 0-7 mM).
D000818:Animals; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology*; D007033:Hypothalamus, Middle / Q000378:metabolism*; D066298:In Vitro Techniques; D007773:Lactates / Q000494:pharmacology; D008297:Male; D011188:Potassium / Q000493:pharmacokinetics* / Q000494:pharmacology; D011773:Pyruvates / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000493:pharmacokinetics* / Q000494:pharmacology; D013004:Somatostatin / Q000378:metabolism*
D007773:Lactates; D011773:Pyruvates; D013004:Somatostatin; D012964:Sodium; D005947:Glucose; D011188:Potassium