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1.
Potassium permeability was monitored in human sweat glands and rat submandibular glands. Acetylcholine increased permeability in both tissues and the responses consisted of transient, calcium-independent and sustained, calcium-dependent components. Amiloride, a drug which inhibits Na(+)-H+ countertransport, impaired the regulation of potassium permeability in sweat glands but not in the submandibular gland. It is suggested that the stimulus-permeability coupling process in the sweat gland may be sensitive to the lowering of internal pH.  相似文献   

2.
Acetylcholine releases calcium from cytoplasmic stores and permits an influx of calcium in salivary acinar cells. The resultant rise in [Ca2+]i causes an increase in potassium permeability which is an important part of the secretory response. We have investigated the effects of 12-0-tetradecanoyl phorbol-13-acetate, a potent activator of protein kinase C, upon this regulation of potassium permeability in superfused pieces of rat submandibular salivary gland. This compound inhibited the initial [Ca2+]o-independent component of the response of acetylcholine but had no effect upon the subsequent [Ca2+]o-dependent phase. This compound does not, therefore, appear to inhibit receptor-regulated calcium influx.  相似文献   

3.
Summary A bradykinin analogue, D-Arg[Hyp3, Thi5, 8, D-Phe7]-Bk, antagonized the vasodilator effect of bradykinin injected close-arterially in the submandibular salivary gland of the cat, without affecting that due to acetylcholine or nerve stimulation. The same analogue also antagonized the hypotensive response to bradykinin injected intravenously in cats and rabbits. We conclude that functional hyperaemia in the submandibular gland of the cat is not due to the release of bradykinin by salivary kallikrein.  相似文献   

4.
T Ikeno  S Hashimoto  H Kuzuya 《Experientia》1982,38(2):251-252
Stimulation by pilocarpine led to a marked increase in amylase activity in the submandibular and sublingual glands and serum, and resulted in a considerable depletion of the enzyme in the parotid gland and pancreas of rats. Parotidectomy reduced these pilocarpine effects. It is concluded that amylase released by pilocarpine from the parotid gland but not from the pancreas elevated the enzyme activity in the submandibular and sublingual glands.  相似文献   

5.
Summary Using an automated system for the analysis of amylase, the release of this enzyme was compared in superfused parotid gland segments from control and reserpine treated rats. Stimulant-evoked amylase release was delayed and of smaller magnitude in the glands of the treated animals and a reduction of the transmembrane K+ gradient caused a smaller and short lasting reduction in Ach-evoked release of amylase in the glands from these animals.This work was supported by grants from the Cystic Fibrosis Research Trust (U.K.), Cystic Fibrosis Foundation (USA) and University of Missouri.  相似文献   

6.
Summary Stimulation by pilocarpine led to a marked increase in amylase activity in the submadibular and sublingual glands and serum, and resulted in a considerable depletion of the enzyme in the parotid gland and pancreas of rats. Parotidectomy reduced these pilocarpine effects. It is conluded that amylaser released by pilocarpine from the parotid gland but not from the pancreas elevated the nzyme activity in the submandibular and sublingual glands.  相似文献   

7.
Summary Acini were enzymatically dissociated from rat submandibular gland and their mucous glycoproteins radiolabelled with14C-glucosamine. Sera from cystic fibrosis patients stimulated the release of labelled TCA/PTA — insoluble material from the cultured acinar cells to a significantly higher degree than did control sera.This work was supported by the Canadian Cystic Fibrosis Foundation and the Sellers Foundation.  相似文献   

8.
Summary Equivalent spaces of42K were measured in fragments of the submandibular gland of 1-, 7-, 14- and 21-day-old and adult rats in the absence and presence of carbachol and the transport inhibitors ouabain and furosemide. The results indicate that the42K space was increased by carbachol in an ouabain-sensitive manner at all ages studied and that part of the secretagogue-stimulated K uptake occurred by way of a furosemide-sensitive transport system in the latter part of the postnatal period and in the adult.  相似文献   

9.
Juvenile hormone bisepoxide (JHB3) and juvenile hormone III (JH III) both inhibited the in vitro production of ecdysteroids by ring glands and brain-ring gland complexes from third instar post-feeding larvae ofDrosophila melanogaster in a reversible manner, although JHB3 had greater efficacy. The JH III and JHB3 precursor, methyl farnesoate, did not affect ecdysteroid production. The in vitro synthesis of total detectable JH (JHB3+JH III+methyl farnesoate) by the corpus allatum portion of the isolated ring gland was also inhibited reversibly in the presence of exogenous JHB3 and JH III, but not by methyl farnesoate. These data indicating negative feedback are in agreement with the accepted dogma of endocrine gland regulation.  相似文献   

10.
We have explored the properties of a Ca2+-dependent cell-signalling pathway that becomes active when cultured equine sweat gland cells are stimulated with ATP. The ATP-regulated, Ca2+-influx pathway allowed Sr2+ to enter the cytoplasm but permitted only a minimal influx of Ba2+. Experiments in which cells were repeatedly stimulated with ATP suggested that Sr2+, but not Ba2+, could become incorporated into the agonist-sensitive, cytoplasmic Ca2+ store. Further evidence for this was provided by experiments using ionomycin, a Ca2+ ionophore which has no affinity for Sr2+.  相似文献   

11.
Summary A wasting syndrome, similar to that occurring after cortisol treatment, was induced in neonatal mice by means of the daily i.p. administration of salivary gland homogenate: 24 h after a single injection of the, homogenate, profuse cell necrosis was observed in the thymic cortex, 48 h later the cortex was devoid of lymphocytes. It is hypothesized that the submandibular glands of mice contain substance which are capable of inducing a cortisol-like effect.We should like to thank Miss Angela Würfler for her careful technical assistance.  相似文献   

12.
In human skin transplanted to the back of 3 strains of immuno-deficient mice the functin of the eccrine sweat glands of the human transplant was tested by topical intradermal application of pilocarine, adrenaline and atropine+pilocarpine. Sweat responses were observed in pre-selected fields of observation by means of video macroscope. The iodine strarch reaction served as an indicator for the appearance of seat sport and permitted the evaluation of areas wetted by sweat in the field of observation. Among 9 animals tested, the hybrids between the CB-17-scid mouse and the BALB/cA-nu mouse (BALB/cA-nu,scid) seemed to exhibit the most consistent seweating response to local pharmacological stimulation. According to histological examination, eccrine sweat glands were preserved in human skin trasplanted into the back skin of the BALB/cA-nu,scid mouse strain. the heterologous, human skin graft provides a novel model permitting, independent of the normal sweat gland innervation, the analysis of moecular receptors of sweat gland cells by which the actions of natural transmitters and pharmacological agents are transduced.  相似文献   

13.
Summary A pheromone-producing gland was discovered in the second abdominal segment of virgin female tobacco beetles,Lasioderma serricorne (Fabricius). The gland duct extends to an orifice below the genital pore and is supported by a rigid invagination of the integument. Hexane extracts of intact pheromone glands were found attractive to male tobacco beetles and also induced high receptor potentials in the olfactory sensilla of the antennae of maleL. serricorne. A surface extract of virgin females proved to be significantly more attractive than an extract of pheromone glands.  相似文献   

14.
Summary The presence of 10–3 M ouabain or furosemide in the perfusate inhibited saliva secretion induced by either isoproterenol (10–5 M) or phenylephrine (10–5 M) from isolated rat submandibular glands and caused characteristic alterations in the electrolyte composition of saliva.  相似文献   

15.
We have demonstrated the presence of estrogen receptor mRNA and the mature protein in the cytoplasm and nucleus, respectively, of a 9,10-dimethyl-1,2-benzathracene-induced submandibular gland tumor in female rats. We have previously shown that progesterone receptors are also present in human salivary gland tumors. These results suggest that endocrine therapy may be effective in treatment of submandibular gland tumors.  相似文献   

16.
Summary The main cellular defence systems against free radical-mediated oxidative stress are significantly reduced in the dige+ive gland of aged (>10 years old) compared to younger (2–4 years old) mussels (Mytilus edulis L.). Moreover, the concentration of lipid peroxidation products (malondialdehyde) is increased in the same age group with respect to younger animals. The obtained data indicate that an impairment of the antioxidant defence systems would render the older animals more susceptible to peroxidative stress, thus supporting the general significance of the free radical theory of aging.  相似文献   

17.
M Uddin  D W Tyler 《Experientia》1978,34(5):609-610
The functional significance of kallikrein in the salivary gland remains unclear partially because of uncertainty over its precise cellular localization. Kallikrein was thought to originate in acinar cells, until recent evidence from cat and rat localized it primarily to the ducts. The possibility that salivary kallikrein may also be located in demilune cells was investigated in this study. - The total kallikrein content of cat submandibular glands was found to be substantially reduced by sampathetic nerve stimulation; whereas parasympathetic stimulation had no significant effect. These biochemical findings did not correlate with morphological studies that revealed almost complete depletion of the demilune cells secretory granules after stimulation of either division of the autonomic nerve supply. This lack of correlation makes it unlikely that kallikrein is present in the demilune cell secretory granules.  相似文献   

18.
Summary Salivary glands with high, low, or no peroxidase activity do not differ in [S14CN] after the i.v. injection of KS14CN, nor do the glands differ from blood and muscle in [S14CN]. The content of SCN in a salivary gland does not mirror the gland's participation in the peroxidase-mediated antimicrobial mechanism.  相似文献   

19.
Summary Numerous inclusion bodies (virus-like particles) were observed in the lumina of the intercellular canaliculi, mucous tubules and intralobular ducts of the opossum submandibular gland. The particles are spherical in outline, show an electron dense core, and are surrounded by a peripheral membrane.  相似文献   

20.
Summary 9 isozymes of esteroproteases were detected by column isoelectric focusing of submandibular gland extracts from four inbred strains of male mice. A marked strain variance in the esteroprotease isozymes was found among the strains.  相似文献   

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