Feeding and Amines Stimulate the Growth of the Salivary Gland following Short-Term Starvation in the Black Field Cricket, Teleogryllus commodus

Abstract

The salivary gland of the black field cricket, Teleogryllus commodus Walker changed size between being starved and fed. Crickets without access to food for 72 h showed a reduction in both wet and dry mass of the glands compared with the glands from continuously fed animals at 72 h. Glands returned to size following ingestion within 10 min. Salivary glands of starved crickets (72 h) were incubated in saline containing either serotonin (5-HT) or dopamine (DA). Glands increased to pre-starvation size after 1 h incubation in situ with either 10−4 moles L−1 5-HT or 10−4 moles L−1 DA, although lower concentrations (10−5 moles L−1) did not affect gland size. From immunohistochemistry, amines appeared to shift from zymogen cells during starvation to parietal cells following feeding. High-performance liquid chromatography showed that serotonin concentration is higher than dopamine in the salivary gland removed from starved and fed crickets, but the quantity of these compounds was not dependent upon feeding state; the amine quantities increased as gland size increased. Further work is necessary to determine what might be the stimulus for gland growth and if dopamine and serotonin play a role in the stimulation of salivary gland growth after a period of starvation.

Unraveling the Interplay of Dopamine, Carbon Monoxide, and Heme Oxygenase in Neuromodulation and Cognition

“…The dopaminergic system plays important roles in neuromodulation including prominent roles in complex neurological functions such as cognition, reward, motivation, and memory. Understandably, the highly complex nature of the dopaminergic system necessitates the existence of intersection points with other signaling pathways fundamental to normal pathophysiological responses. − For example, the dopaminergic system is implicated in injury, starvation and feeding, temperature changes, and cardiometabolism, among many others. As such, understanding how other signaling pathways intersect with the dopaminergic system is of great significance.…”