Blood pressure and heart rate responses of SHR and WKY rat pups during feeding

These studies measured changes in blood pressure and heart rates of 15-day-old SHR and WKY rat pups immediately following milk ingestion using three different methods of milk delivery. In the first experiment milk ejections were induced, using IV oxytocin, from the pups' natural mothers, while in the second experiment ejections were elicited from Marland Farms Wistar foster mothers. In the last experiment cow's milk was delivered using tongue cannulas and no mother was present. In each case we found that the dramatic increases in blood pressure associated with milk ingestion were larger in the SHR pups, while heart rate changes tended to be larger in the WKY. We also found that the dynamics of these cardiovascular responses to feeding were significantly altered by the presence of the mother.