Expression pattern of calcium influx receptors in small intestine of pregnant and non-pregnant sheep

A study was conducted to investigate the expression pattern of calcium influx receptors in the small intestine of Nellore Brown sheep. Tissue samples from different parts of small intestine were collected from 18 pregnant (early, mid and late pregnant, 6 each) and 6 non-pregnant ewes from local slaughterhouse, Tirupati and processed for immunohistochemical studies. Calcium influx receptors revealed strong reaction in the tissue samples of pregnant as compared to non-pregnant animals in duodenum and jejunum. The expression pattern of calcium influx receptors was higher in late gestation than early, mid and non-pregnant animals whereas, transient receptor potential vanilloid channel type 5 (TRPV5) immunore activity was moderate in small intestine and more involved in calcium transport via paracellular pathway. Serum calcium level was higher (P<0.05) in non-pregnant as compared to pregnant animals and they were 8.29±0.54, 5.72±0.19, 4.98±0.25, 3.75±0.14 mg/dL in non-pregnant, early, mid and late pregnant animals respectively. It was concluded that duodenum and jejunum were the principal active sites of calcium absorption in sheep.Thus it indicated that ileum hadnoroleincalcium absorption viatranscellularpathway in pregnant ewes.