Alberto B. Houssay

Changes in human parotid salivary protein and sialic acid levels during pregnancy.

Saliva was collected with a Carlson-Crittenden device, under citric acid stimulation, in 107 pregnant women, 9 puerperal and 7 non-pregnant controls. No significant changes were found in salivary flow rate, pH and amylase levels. The total protein levels were decreased during pregnancy and the puerperium. The sialic acid levels decreased gradually but markedly during pregnancy, returning to normal levels in the puerperium. These changes in parotid saliva may be related to the hormonal changes of pregnancy.

On the mechanism of the hypertrophy of the retrolingual glands of the rat induced by incisor amputations

Abstract The role of the autonomic nervous system in the retrolingual hypertrophy induced by repeated bilateral amputations of the inferior incisor was studied in white male rats and compared with its role in the hypertrophy of the submaxillary glands. Parasympathetic denervation through bilateral sectioning of the chordalingual nerve produced atrophy of the submaxillary and retrolingual glands, it prevented completely the hypertrophy of the retrolingual glands following amputations of the incisor, but it did not prevent the hypertrophy of the submaxillary glands. Sympathetic denervation through bilateral resection of the superior cervical ganglia produced atrophy of the submaxillary but not of the retrolingual glands and it did not prevent hypertrophy of either the retrolingual or the submaxillary glands after incisor amputations. The hypertrophy of the submaxillary gland following incisor amputations was prevented only by denervation of both the sympathetic and parasympathetic nerves, it being transmitted by both nerves. The hypertrophy of the retrolingual gland following incisor amputations is transmitted only by the parasympathetic innervation.

Acid Glycosaminoglycans and Sialic Acid Content in Salivary Glands of Rats

Sialic acid concentrations were strong in retrolingual and moderate in submaxillary glands. Uronic acid concentrations were high in retrolingual, intermediate in parotid, and low in submaxillary glands. The major fraction in the submaxillary and parotid glands was hialuronic acid, whereas in the retrolingual gland, the major fractions were glycoproteins and dermatan-sulfate.

Enzymes of the tricarboxylic cycle in periodontal tissues of the guinea pig

Abstract The enzymes of the tricarboxylic cycle: fumarase, aconitase, malic and isocitric dehydrogenases and the malic ancilliary enzyme were determined in the gingiva, periosteum and periodontium of the inferior incisor region in guinea pigs and compared with their activities in the liver, kidneys, adrenals, pituitary and testes of the same animals. The activity of all these enzymes in the periodontal tissues was very high. It is suggested that the high metabolism indicated by these intense oxidative activities may bring a mobilization of substrates with possible activation of other enzymatic systems.

Effects of thyroid function on submaxillary gland sensitivity to autonomic nervous drugs

The effect of changes in thyroid function on the action of autonomic drugs upon the secretion of saliva by the submaxillary glands was studied in male Wistar rats. Hyperthyroidism was induced by the sc administration every 12 h of 10/μg/100 g bw of L-triiodothyronine; hypothyroidism was induced by surgical thyroidectomy 2 weeks before the experiments. The dose-response curves to increasing doses of isoprenaline, norepinephrine or methacholine showed in hyperthyroid animals increased salivary secretion, while in hypothyroid animals the dose-response to the drug was reduced. The threshold dose for isoprenaline was reduced in hyperthyroid animals and increased in hypothyroid ones. The threshold dose for norepinephrine did not change in hyperthyroid or hypothyroid animals while that for methacholine was decreased in hyperthyroid ones. When norepinephrine was giyen to α-blocked animals (with phentolamine) the difference in the dose-response curves between hyperthyroid and control animals was increased. But when norepinephrine was given to β-blocked animals (with propranolol) the difference between the dose-response curves of hyperthyroid and control animals disappeared. The results above presented show that the sensitivity of the submaxillary salivary glands of rats to some adrenergic and cholinergic drugs was altered by the thyroid hormone. The effect was greater in the responses mediated by beta receptors. The structural changes in these glands may have some role in these effects.

Enzymes of glycolytic cycle in periodontal tissues of the guinea pig

Abstract The enzymes of the glycolytic cycle: phosphohexoisomerase, aldolase, phosphoglycerokinase and glucose-6-phosphatase were determined in the gingiva, periosteum and periodontium of the mandibular incisor region in the guinea pig and compared with their activities in the liver, kidneys, adrenals, pituitary and testes of the same animal. The enzymatic activities of the periodontal tissues were generally high. The phosphohexoisomerase and the aldolase activity in periosteum and periodontium was as high as in the other tissues. The phosphoglycerokinase activity of periosteum and gingiva were higher than in the other tissues. The glucose-6-phosphatase activity in periosteum and periodontium was about half as high as the liver activity.

Cervical mucus and serum ascorbic and dehydroascorbic acid concentrations during the menstrual cycle.

Abstract Cervical mucus and serum ascorbic and dehydroascorbic acid concentrations were studied in 89 women with diphasic cycles. A modification of the Roe and Kuether technique was used, which allowed differentiation between three values: (1) total RK (+) substances; (2) pre-existent RK (+) substances (including dehydroascorbic acid and uronic acid containing substances); and (3) the real ascorbic acid by the difference between the two former values. Pre-existent RK (+) substances concentration in cervical mucus or in serum has a bell-shaped regression curve, which is higher in the middle of the cycle and lower at the beginning and at the end. Real ascorbic acid concentration in cervical mucus or in serum is lower in midcycle and higher at the beginning and end. The total RK (+) substances concentration (or total vitamin C) depended on the algebraic sum of the other two values. In cervical mucus, in which the pre-existent fraction is predominant, the curve is also bell-shaped and similar to the one of that fraction. In serum there was a balance between the two opposite changes and the total RK (+) substances concentration did not change significantly during the menstrual cycle. The importance of the sex steroids, especially the estrogens, as factors which determine the above described changes is discussed.

Effects of Estrogens on Submaxillary Glands in Mice

Estradiol benzoate in daily doses of 3, 10, or 30 μg was administered for one month to castrated or to castrated-adrenalectomized mice. Histologic and histometric studies of the submaxillary glands were performed. There was submaxillary hypertrophy caused by the granular tubules in the estradiol-injected mice. Adrenalectomy did not interfere with this effect.

Thyroid hormone modulation of VIP’s induced salivary secretion in the submaxillary glands of rats

The effect of changes in thyroid function upon vasoactive intestinal peptide (VIP) induced secretion of saliva were studied in male Wistar rats. Hyperthyroidism was induced by the sc administration every 12 h of 10 μg/100 g bwof l-triiodothyronine; hypothyroidism was induced by surgical thyroidectomy 2 weeks before the experiments. Preganglionar parasympathetic denervation was induced by sectioning the chorda tympani on the left side. The dose-response curves to increasing doses of VIP showed in the hypothyroid animals increased salivary secretion, while in the hyperthyroid ones the dose-response to the drug was reduced. This effect was seen on both sides, the denervated and the control ones. In the denervated glands there was a marked hypersensitivity to the administration of VIP producing greater responses with the same doses, in the 3 groups of animals. The negative modulation by thyroid hormones of the salivary response to VIP administration is compared with the positive modulation they induce in the salivary response to β-adrenergic and cholinergic drugs.

Influence of the Adrenal Glands on the Sialic Acid Content of Submaxillary and Retrolingual Glands in the Rat

Adrenalectomy decreased sialic acid content in the submaxillary and retrolingual glands of normal male rats. The administration of cortisol acetate to adrenalectomized rats increased submaxillary and retrolingual sialic acid content; administration of desoxycorticosterone acetate decreased the submaxillary gland content but not the retrolingual gland content.