Ionic distribution in dopamine-stimulated NaCl fluid-secreting cockroach salivary glands
Gupta, B.L.; Hall, T.A.
American Journal of Physiology 244(2): R176-R186
1983
ISSN/ISBN: 0002-9513 PMID: 6824102 Document Number: 197699
The compound, racemose, innervated salivary glands of Periplaneta americana (L.) closely resemble in structure and function the mammalian salivary glands. The quantitative distribution of Na, K, Cl, Ca, Mg, P and S was investigated in the P-cells secreting isotonic NaCl and in duct lumens by using electron probe X-ray microanalysis of frozen-hydrated and frozen-dried cryosections. During passage through the ducts, the primary saliva was modified by an absorption of NaCl: more in unstimulated than in stimulated glands. It is suggested that the cells have a Na-K-ATPase both in the apical and basal cell membrane, as in vertebrate choroid plexus, and dopamine might increase the K and Na conductance of the basal cell membrane.