Galanin‐like innervation of rat submandibular and sublingual salivary glands: Origin and effect on acinar cell membranes

Journal of Comparative Neurology - Tập 317 Số 3 - Trang 271-282 - 1992
Lukasz M. Konopka1, Víctor May2, Cynthia J. Forehand3
1Department of Anatomy and Neurobiology, University of Vermont, College of Medicine, Burlington 05405.
2Department of Anatomy and Neurobiology, University of Vermont College of Medicine, Burlington, Vermont 05405
3Dept. of Anatomy and Neurobiology, University of Vermont College of Medicine, Burlington, VT 05405

Tóm tắt

AbstractThe distribution and source of a galanin‐like innervation of rat salivary glands has been examined. Additionally, submandibular and sublingual acinar cell membrane responses to galanin or a cholinergic agonist were studied. Galanin‐immunoreactive fibers were observed throughout the submandibular and sublingual glands in association with ducts and acini. A subset of submandibular ganglion cells expresses galanin immunoreactivity. Parasympathectomy resulted in a marked decrease in galanin immunoreactivity in the glands. Sympathectomy resulted in marked reduction of dopamine β‐hydroxylase immunoreactivity with no appreciable change in galanin immunoreactivity. Retrograde labeling experiments demonstrated that galanin‐immunoreactive sensory neurons in the trigeminal ganglion do not innervate the submandibular or sublingual gland. These results indicate that the galanin‐like innervation of rat salivary glands is derived from parasympathetic nerves to the glands.Since rat sublingual glands contain largely mucous acini while rat submandibular gland acini are seromucous, electrophysiological responses to galanin and the muscarinic agonist, bethanechol, were compared. Agonist‐induced voltage shifts varied between the two glands. The galanin‐induced response at the level of the resting membrane potential in submandibular acinar cells was a hyperpolarization, while that in sublingual acinar cells was a depolarization. There was also a greater voltage dependence to the galanin‐induced submandibular response than to the sublingual response. Differences were also noted in the acinar cell response to cholinergic stimulation between these glands.These results demonstrate the existence of a galanin‐like innervation to salivary glands that may be functionally relevant. Moreover, the results challenge the idea that agonist‐induced membrane responses are similar among acinar cells of different glands.

Từ khóa


Tài liệu tham khảo

10.1016/0014-5793(88)81131-1

10.1111/j.1365-2036.1989.tb00252.x

10.1177/00220345870660S204

Bennett H. P. J., 1981, Peptides, 785

10.1042/bj1751139

Cheung A., 1985, Distribution of galanin‐like immunoreactivity in the respiratory tract of the pig, J. Pathol., 145, A113

Ch'ng J. L., 1984, Distribution of galanin immunoreactivity in the central nervous system and gastrointestinal tract, Dig. Dis. Sci., 29, 17S

10.1177/00220345870660022301

10.1016/0306-4522(88)90110-8

10.1111/j.1748-1716.1989.tb08684.x

10.1523/JNEUROSCI.06-03-00837.1986

Emmelin N., 1967, Handbook of Physiology, Sect. 6: Alimentary Canal, Vol. II: Secretion, 595

Forehand C. J., 1989, Rat sublingual and submandibular gland cells differ in their responses to both galanin and bethanechol, Soc. Neurosci. Abstr., 15, 741

Frierson F. A., 1989, Galanin immunoreactivity in parasympathetic postganglionic neurons in rat salivary glands, Soc. Neurosci. Abstr., 15, 741

10.1038/283393a0

10.1177/00220345870660020201

10.1111/j.1471-4159.1966.tb09873.x

10.1016/0306-4522(88)90334-X

10.1007/BF00219743

10.1113/jphysiol.1989.sp017523

10.1016/0304-3940(89)90279-6

10.1007/BF00218883

10.1111/j.1748-1716.1955.tb01258.x

10.1073/pnas.77.3.1651

Lundberg J. M., 1988, Handbook of Chemical Neuroanatomy, Vol. 6: The Peripheral Nervous System, 391

10.1007/BF02139773

10.1152/physrev.1976.56.3.535

10.1007/BF01869896

10.1016/0024-3205(89)90297-X

Schepp W., 1990, Galanin inhibits gastrin release from isolated rat gastric G‐cells, Am. J. Physiol., 258, G596

Shackleford J. M., 1962, Structure and carbohydrate histochemistry of mammalian salivary glands, Am. J. Anat., 3, 25, 10.1002/aja.1001110104

10.1007/BF00492515

10.1007/BF01680455

10.1016/0014-5793(83)80033-7

10.1111/j.1748-1716.1986.tb07830.x

10.1111/j.1748-1716.1980.tb06626.x