抄録
Our recent anatomical study shows that the sensory nerve travels in both the sympathetic and parasympathetic nerve supplies to the submandibular gland of the rat. In the present study we analyze afferent neural activities in the sensory nerve from the submandibular gland in urethane-anesthetized rats. The following results were obtained: 1) The afferent activity could be recorded from both sympathetic and parasympathetic routes; 2) both afferents responded to mechanical pressure applied onto the gland; 3) when back pressure was applied from the main excretory duct, both afferents showed tonic impulse discharges at pressure of higher than 100 mmHg; 4) the threshold pressure was little lower than the maximal secretory pressure which was induced by electrical stimulation of the parasympathetic secretory nerve (the chorda tympani); 5) the sensory nerve in the parasympathetic, but not sympathetic, nerve supply responded to mechanical pressure on the main excretory duct; 6) the sensory nerve in the sympathetic nerve supply discharged after ligation of the artery to the gland. Our results suggest that the sensory nerves in the parasympathetic nerve supply innervate the submandibular gland and its main duct, whereas those in the sympathetic nerve supply innervate the gland and its artery. The nerves innervating the duct are responsive to relatively strong duct pressure compared to the maximum secretory pressure. The nerves innervating the artery may contribute control of blood flow changes. [J Physiol Sci. 2007;57 Suppl:S237]
