Evaporative Cooling in the Rat: Differences Between Salivary Glands as Thermoregulatory Effectors

1971 ◽  
Vol 49 (6) ◽  
pp. 573-580 ◽  
Author(s):  
F. Reed Hainsworth ◽  
Edward M. Stricker
Keyword(s):  
Heat Stress ◽  
Salivary Glands ◽  
Sodium Concentration ◽  
Fundamental Difference ◽  
Surgical Removal ◽  
Body Temperature Regulation ◽  
Parotid Glands ◽  
Parotid Saliva ◽  
Evaporative Water ◽  
Submaxillary Glands

Rats cool themselves in the heat by evaporating saliva groomed onto their body surfaces. Previous reports indicated that surgical removal of the submaxillary glands severely impaired evaporative water loss and body temperature regulation, whereas parotid desalivation had little effect. In the present experiments saliva was collected directly from the oral cavities of rats exposed to heat stress and was identified by its sodium concentration to determine the roles of individual salivary glands as thermoregulatory effectors. The fundamental difference between the glands was that submaxillary secretion was initiated at a lower level of hyperthermia (38.5 °C) than parotid secretion (40.0 °C), and thus made a greater contribution to thermoregulation. For example, normal rats secreted only submaxillary saliva at an ambient temperature of 36 °C and secreted three times more submaxillary saliva than parotid saliva at 40 °C. These results indicate that the submaxillary glands are primary thermoregulatory effectors of rats during heat stress, and that the parotid glands provide supplementary secretion only during pronounced hyperthermia.

Peripheral Neural Control of Thermoregulatory Salivary Secretion in the Rat

1973 ◽  
Vol 51 (3) ◽  
pp. 213-219 ◽  
Author(s):  
Karin D. Rodland ◽  
F. Reed Hainsworth
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
Neural Control ◽  
Sympathetic Nerves ◽  
Sodium Concentration ◽  
Salivary Secretion ◽  
The Body ◽  
Parotid Glands ◽  
Submaxillary Glands ◽  
Relative Contribution

Rats exposed to heat stress increase heat loss by evaporating saliva groomed onto body surfaces. Both the submaxillary glands and the parotid glands secrete saliva in response to heat, and both are innervated by parasympathetic and sympathetic nerves. The results of previous investigations have indicated that the parasympathetic nervous supply is of major importance in controlling salivary secretion from the submaxillary glands of heat-stressed rats. In this study saliva was collected directly from the mouth of rats exposed to heat stress, and the saliva was analyzed for sodium concentration to determine the relative contribution of the submaxillary–sublingual and parotid glands. The results indicate that parasympathetic denervation of either the submaxillary glands or the parotid glands greatly reduces secretion from that gland, without affecting the body temperature at which secretion begins. Following sympathetic denervation, salivary secretion seems to start at a higher body temperature.

Evaporative Cooling in the Rat: Further Consideration of Functional Differences Between Salivary Glands

1972 ◽  
Vol 50 (2) ◽  
pp. 172-175 ◽  
Author(s):  
F. Reed Hainsworth ◽  
Edward M. Stricker
Keyword(s):  
Heat Stress ◽  
Salivary Glands ◽  
Evaporative Cooling ◽  
Salivary Secretion ◽  
Female Rats ◽  
Male Rat ◽  
Parotid Saliva ◽  
Functional Differences ◽  
The Difference

Previous reports indicated that submaxillary saliva, but not parotid saliva, was crucial to thermoregulation in the male rat exposed to inescapable heat stress, and emphasized the lower level of hyperthermia associated with the initiation of submaxillary secretion as one factor accounting for the difference between individual salivary glands. The present results indicated that submaxillary saliva was also crucial to the survival of female rats exposed to moderate heat stress, yet submaxillary and parotid secretions were increased at comparable levels of hyperthermia. Thus, it appears that the most important difference between the glands is not the level of hyperthermia associated with increased salivary secretion but the amount of fluid that is provided once secretion is begun.

Temporal Reduction in Size of Salivary Acinus in Rats Induced by Theophylline

2005 ◽  
Vol 33 (2) ◽  
pp. 218-224 ◽  
Author(s):  
Satoru Kajikawa ◽  
Ayano Takeuchi ◽  
Aisuke Nii ◽  
Hiroyuki Nakayama ◽  
Kunio Doi
Keyword(s):  
Salivary Glands ◽  
Time Course ◽  
Water Channel ◽  
Phosphodiesterase Inhibitor ◽  
Repeated Administration ◽  
Receptor Activation ◽  
Parotid Glands ◽  
Aquaporin 5 ◽  
Submaxillary Glands ◽  
Immuno Histochemistry

Repeated administration of theophylline, a phosphodiesterase inhibitor, induces the enlargement of the salivary glands in rats. Time-course changes after a single administration of theophylline were examined in the salivary glands, including phosphodiesterase enzyme activity, and the expression of aquaporin 5 (AQP5), a water channel. We also examined the contribution of β-adrenergic receptors to theophylline-induced salivary changes. Male F344 rats were given 50 mg/kg of theophylline intraperitoneally either alone or concurrently with a 10 mg/kg subcutaneous injection of propranolol. After treatment with theophylline alone, the weight and histology of the submaxillary and parotid glands were examined. Phosphodiesterase activity and AQP5 were detected by enzyme- and immuno-histochemistry, respectively. At 4 hours, 8 hours, or both, organ weights were decreased with depletion of secretory vesicles in the acinar cells. In the submaxillary glands, reduced activity of phosphodiesterase and increased expression of AQP5 in the intercalated ducts were observed at 4 hours. When co-administered, propranolol partially abolished theophylline-induced glandular reduction. These results suggest that the theophylline-induced transient reduction in size of the salivary glands is attributable not only to phosphodiesterase inhibition but also to β-adrenergic receptor activation and that the intercalated ducts in submaxillary glands play a role in the production of saliva.

The development of parotid salivation in the lamb

1961 ◽  
Vol 12 (6) ◽  
pp. 1126 ◽  
Author(s):  
AD Wilson ◽  
DE Tribe
Keyword(s):  
Body Weight ◽  
Electrical Stimulation ◽  
Parotid Gland ◽  
Histological Examination ◽  
The Body ◽  
Parotid Glands ◽  
Fresh Weight ◽  
Parotid Saliva ◽  
Submaxillary Glands ◽  
Stimulation Of

The development of the parotid gland was studied in lambs reared under the following three dietary conditions: (a) lambs freely grazed with their ewes; (b) lambs hand-reared on milk and hay; (c) lambs hand-reared on milk alone. Weekly measurements were made of the saliva flowing from the cannulated parotids of two anaesthetized lambs from each group, during reflex and electrical stimulation of their glands. The fresh weights of the parotid and submaxillary glands and of the four stomachs were also recorded. Before 4 weeks of age, all the parotid glands were physiologically immature, secreting only 0.1–0.2 g saliva/g parotid tissue/min. The parotids of the grazing lambs developed rapidly from 4 to 6 weeks of age and reached adult capacity of 0.50–0.65 g/g/min between 7 and 10 weeks of age. The parotids of the lambs receiving millr and hay developed more slowly than the grazing lambs, while the parotids of the lambs receiving milk only scarcely developed at all. The histological examination of these glands showed that the parotids of the 2-week-old lambs were immature. Differentiation in the grazing group occurred at 4–6 weeks of age, while no differentiation occurred in the lambs fed milk only. The rate of flow of parotid saliva from all lambs was significantly correlated with the fresh weight of rumen tissue. The parotid gland increased in weight in relation to the rumen weight and not to the body weight.

Secretion by salivary glands deficient in acini

1961 ◽  
Vol 201 (5) ◽  
pp. 939-942 ◽  
Author(s):  
C. A. Schneyer ◽  
L. H. Schneyer
Keyword(s):  
Salivary Glands ◽  
Flow Rate ◽  
Secretory Activity ◽  
Sodium Concentration ◽  
Normal Adult ◽  
Parotid Glands ◽  
Experimental Conditions ◽  
Sodium And Potassium

Rat submaxillary and parotid glands deficient in acini were obtained by selecting normal early postnatal animals or by ligating gland excretory ducts in adult animals. Acinar deficiency under these conditions was histologically confirmed for submaxillary and demonstrated for parotid glands. Glands with pronounced acinar deficiency secreted in response to pilocarpine. Flow rate, in the early postnatal state, approximated that from normal adult glands, whereas from ligated glands, flow was frequently reduced. In the two experimental conditions, potassium levels of the secretions from both glands were uniformly high (about 50 mEq/liter), approximating normal adult submaxillary levels. Sodium concentration was altered from normal only in parotid secretion of early postnatal animals where it was reduced, and in submaxillary secretion of ligated gland where it was elevated. These results, while not establishing the extent of secretory activity in the normal adult condition, demonstrate the capacity of ductal elements to secrete water, sodium, and potassium at rates frequently approaching those of normal adult glands.

Partial Purification of a Specific Plasminogen Activator from Porcine Parotid Glands

1974 ◽  
Vol 31 (03) ◽  
pp. 403-414 ◽  
Author(s):  
Terence Cartwright
Keyword(s):  
Nucleic Acid ◽  
Salivary Glands ◽  
Plasminogen Activator ◽  
Protein Interactions ◽  
Partial Purification ◽  
Protein Protein Interactions ◽  
Parotid Glands ◽  
Two Stage ◽  
Preliminary Characterization ◽  
Specific Inhibitors

SummaryA method is described for the extraction with buffers of near physiological pH of a plasminogen activator from porcine salivary glands. Substantial purification of the activator was achieved although this was to some extent complicated by concomitant extraction of nucleic acid from the glands. Preliminary characterization experiments using specific inhibitors suggested that the activator functioned by a similar mechanism to that proposed for urokinase, but with some important kinetic differences in two-stage assay systems. The lack of reactivity of the pig gland enzyme in these systems might be related to the tendency to protein-protein interactions observed with this material.

FUNCTIONAL DISORDERSOF THE SALIVARY GLANDS IN PATIENTS WITH COMPRESSION AND DISLOCATION DYSFUNCTION OF THE TEMPOROMANDIBULAR JOINT AND THEIR CORRECTION

2021 ◽  
Vol 74 (7) ◽  
pp. 1695-1698
Author(s):  
Oleg V. Rybalov ◽  
Pavel I. Yatsenko ◽  
Olga Yu. Andriyanova ◽  
Elena S. Ivanytska ◽  
Maria A. Korostashova
Keyword(s):  
Parotid Gland ◽  
Salivary Glands ◽  
Functional State ◽  
Oral Fluid ◽  
Healthy Individuals ◽  
Parotid Glands ◽  
Posterior Teeth ◽  
Fluid Content ◽  
Lower Jaw ◽  
Before And After

The aim: Is to assess the functional state of parotid glands and general secretion in patients with compression, dislocation dysfunction of TMJ, to correct the revealed disorders. Materials and methods: We examined 46 patients with dysfunction of TMJ. Examination included TMJ zonography and salivary glands sonography. We studied the general and parotid secretion, transparency, viscosity, pH of the oral fluid and the secretions of the parotid glands before and after treatment. The treatment of dysfunction and hyposialosis included the repositioning of the articular heads of the lower jaw in the correct anatomical position, the use of a repositioning plate on the posterior teeth at the compression side of the articular head, bougienage of the duct of the parotid gland, administration of 10% magnesium-mineral solution of bischofite into the gland. Results: In patients with TMJ dysfunction, a significant decrease in the oral fluid content was noted before treatment. The saliva transparency was reduced, the viscosity was increased, the pH was slightly acidic. A study, which was carried out a month after completion of the course of treatment showed that all the studied parameters corresponded to those in healthy individuals. Conclusions: The study confirmed that in compression and dislocation dysfunction of TMJ, there are disorders of the functional state of the salivary glands.

scholarly journals CYTOLOGICAL LOCALIZATION OF NORADRENALINE, MONOAMINE OXIDASE AND ACETYLCHOLINESTERASE IN SALIVARY GLANDS OF DOG

1966 ◽  
Vol 14 (6) ◽  
pp. 483-490 ◽  
Author(s):  
MOTOHATSU FUJIWARA ◽  
CHIKAKO TANAKA ◽  
HIROSHI HIKOSAKA ◽  
TADAO OKEGAWA
Keyword(s):  
Monoamine Oxidase ◽  
Salivary Glands ◽  
Acetylcholinesterase Activity ◽  
Muscle Layer ◽  
Nerve Fibers ◽  
Autonomic Nerve ◽  
Secretory Cells ◽  
Monoamine Oxidase Activity ◽  
Parotid Glands ◽  
Cytological Localization

The cytological localization of noradrenaline, monoamine oxidase and acetylcholinesterase was examined in the salivary glands of the dog. The noradrenaline-fluorescent nerve fibers surrounded the secretory acini of the submaxillary, sublingual and parotid glands, but the density in the sublingual gland was much less than in the other two glands. Noradrenaline fluorescence was not seen in the cytoplasms of the acinar cells nor in the vicinity of the excretory ducts. Intense fluorescence was present outside the smooth muscle layer in various sized arteries. The distribution of monoamine oxidase activity was different from that of noradrenaline fluoresence. All the cells of the secretory acini and the excretory ducts were evenly stained. The distribution of fibers showing acetylcholinesterase activity was different from that of noradrenaline-fluorescent fibers only in that the former fibers were present around the excretory ducts as well. The composition of secretory cells in the submaxillary and sublingual glands is different in dogs and rats. However, the cytological localization of noradrenaline, monoamine oxidase and acetylcholinesterase activities in the salivary glands of the dog was essentially similar to those of the rat. It was concluded, therefore, that the autonomic nerve supply to the salivary glands does not correlate with the type of secretory cells.

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