Kan suksa nathi khong tai thimi khwam sam phan to attra metabloic nai krabu plak thi dai rap khwam khriat nuang chak khwam ron yang chiap phan.

During animals exposed to heat, there were increases in heart rate, respiratory rate and rectal body temperature without any alteration in packed cell volume and plasma volume. The turnover rate and pool size of both 3 3H glucose and U- 14c glucose increased while the glucose carbon recycling was reduced significantly (P<0 01). Plasma glucose concentration also increased significantly at 3rd h. of heat exposure (p<0.5). Renal function studies showed that although GFR slightly increased, the E-RPF did not changee during heat exposure. Plasma urea, Na+, K+ and Cl- concentrations did not change while the significant increases in total plasma protein and plasma creatinine concentrations were detected after 2 h. of heat exposure (p<0.05). During animal exposed to heat, there was negative correlation between plasma protein concentration and urinary total nitrogen excretion during control period. Plasma creatinine concentration and urinary non urea nitrogen excretion (p<0.01). However, no relationship was observed during heat exposure period. The fractional excretion of K+, Cl-, Ca2+ and Pi increased particularly at the 1st h. of heat exposure and decreased gradually with a concomitant decrease in urine flow rate. The FENa have a tendency to decrease during heat exposure. There was no correlation between plasma glucose concentration and fractional excretion of all electrolytes during both control and heat exposure period. Plasma inorganic phosphate reduced markedly at the 3rd h. of heat exposure (p<0.01). No specific changes of these parameters were detected in animal during control period. Present results on glucose metabolism suggested that during animal exposed to heat, there was an increase in metabolic rate but decrease in gluconeogenesis. Plasma protein and creatinine concentrations increased due to muscle protein breakdown. Heat load had an effect on renal functions particularly electrolyte excretions. There was no relationship between change of renal function and glucose metabolism.