reflexes of dogs with permanent parotid gland fistulee, we have had the McGill University, Montreal, Canada.)

Transcription

1 96 6I2.442:6I2*3I3*I THE EFFECT OF PARATHYROID HORMONE AND OF IRRADIATED ERGOSTEROL UPON THE CALCIUM CONTENT OF THE PAROTID SALIVA OF THE DOG. By L. ANDREYEV AND L. I. PUGSLEY. (From the Departments of Biochemistry and Physiology, McGill University, Montreal, Canada.) (Received August 3, 1933.) BAXTER [1932, 1933] showed that the inorganic composition of the parotid saliva of the dog varied with the stimulus used, and that the saliva secreted by means of pilocarpine stimulation had a lower concentration of calcium than the secretion stimulated by means of meat powder. He considered pilocarpine as a special artificial stimulus which provoked a particular activity of the salivary glands different from that activated by normal reflex stimulation. De Beer and Wilson [1932] have shown recently in acute experiments, using pilocarpine as a stimulus for the secretion, that the intravenous injection of calcium chloride caused an increased concentration of calcium in the parotid saliva of the dog, while the injection of sodium chloride, potassium chloride or potassium carbonate had little effect in altering the composition of the saliva. Werther [1886] found the concentration of calcium in the parotid saliva of the dog to be approximately twice that of the serum calcium. Hubbel and Bunting [1932] found no consistent changes in the calcium or phosphorus concentration of human saliva following viosterol treatment, and Bunting and Wixon [1917] were unable to alter the calcium content of human saliva by feeding a high calcium diet for a period of 2 weeks. Their values for the calcium content of human mixed saliva were approximately the same as for the serum calcium. Clark and Shell [1927] also came to the conclusion that there was no correlation between the diet and the composition of human saliva. In the course of some work we have been doing in this laboratory on the effect of alterations in the serum calcium level upon the conditioned reflexes of dogs with permanent parotid gland fistulee, we have had the

2 CALCIUM CONTENT OF SALIVA. opportunity to study the effect of these two potent serum calcium raising principles (namely, parathyroid hormone and irradiated ergosterol) upon the calcium content of the parotid saliva. The authors are indebted to the Otosclerosis Committee of the American Otological Society for financial assistance; to Eli Lilly and Co. for the parathormone; and to Mead Johnson and Co. for the irradiated ergosterol used in these experiments. METHODS. The saliva was collected and the solutions administered by methods devised by Pavlov and adequately described by Baxter [1932]. The various stimuli were given to the dog continuously for a definite length of time-usually 3 or 10 min., depending upon the volume secretedand then an interval of 10 min. was allowed before the stimulus was repeated. In the case in which pilocarpine hydrochloride was used, the drug was injected intravenously (0.3 mg./kg. body weight) and the collecting tube was attached immediately. In these experiments it was found that the rate of the secretion fell off rapidly after about 4 min., hence we took as our first sample the quantity secreted in this time and as the second the amount which was secreted in the following 10 mn. At the end of this time the secretion had practically ceased. The calcium was determined in the saliva by the method of Krasnov, Karshan and Krejci [1932], and the method of Clark and Collip [1925] was used for the serum calcium. The parathyroid hormone was injected intramuscularly and the saliva collected hours after the injection, or-as in the case of dog 2-when the serum calcium was increased as a result of a series of injections. The ergosterol (Mead Johnson's 10,000 X) was given in the food in doses of 0 5 c.c. daily until the serum showed a definite increase in calcium concentration. This usually required a period of days. At no time was sufficient of either preparation given to cause overdosage symptoms. RESULTS. The results are shown in Table I. The control values of dogs 1 and 2 represent the average values of four different experiments, while those under ergosterol and parathyroid hormone are single experiments. Dog 3, with a double parotid fistula, was kindly loaned to us by Dr H. B ax t er, and was used as a check against the other two, since this dog had never received either parathyroid hormone or irradiated ergosterol. PH. LXXX. 7 97

3 98 a ~~~~~~mg./ L. ANDRE YE V AND L. I. PUGSLEY. Saliva Ca Serum Volume c.c./min. mg./100 c.c. Ca A B A B 100 c.c. TABLE I. The effect of parathyroid hormone and of irradiated ergosterol upon the calcium content of the parotid saliva. Increase in saliva Ca Dog 1 Control Parathormone (100 units) Irradiated ergosterol Sodium chloride-5 p.c. solution. Control Parathormone (100 units) Irradiated ergosterol Hydrochloric acid-0-25 p.c. solution. Control Parathormone (100 units) Irradiated ergosterol Control Parathormone (100 units) Irradiated ergosterol Dog 2 Control Parathormone (100 units) Irradiated ergosterol Control Irradiated ergosterol * Dog 3 A indicates stimulus given first time Sodium chloride-5 p.c. solution Hydrochloric acid-0-25 p.c. solution Increase, in serum A B Ca B indicates same stimulus repeated. It is noted that the volume of saliva secreted in a minute for each stimulus is quite constant for each dog, for the first and second trials respectively, except in the case of pilocarpine where the rate of secretion falls off rapidly during the last 10 min. of the experiment. The control values for the concentration of calcium in the saliva vary with the stimulus used, and in all cases are found to be over three times the serum

4 .CALCIUM CONTENT OF SALIVA. calcium, except in the case of pilocarpine where a lower concentration is found than with the other stimuli. When the serum calcium is increased as a result of parathyroid hormone or ergosterol administration, the saliva calcium shows a marked increase with each stimulus used. For example, in the case of dog 1, using sodium chloride as a stimulus, the increase above the control saliva calcium is 12-3 and 15*1 mg./100 c.c. in the case of parathyroid hormone, and 11-5 and 9-5 mg./100 c.c. in the case of irradiated ergosterol; while the serum calcium values are only 3-4 and 3-3 mg./100 c.c. above the control levels. In nearly every case the rise in saliva calcium is well above the rise in serum calcium, and apparently no distinction can be made between the hormone and the ergosterol in bringing about this increase. The rise in saliva calcium following parathyroid administration is interesting in that it may serve as a measure of the potency of parathyroid gland extracts, especially on small dogs or cats where the taking of blood presents certain difficulties. We are unable at present to offer an explanation of the mechanism of this rise in saliva calcium following parathyroid hormone and ergosterol administration. It is interesting to note in this connection that Parhon and Cahane [1932] found the calcium content of gastric juice of dogs slightly increased as a result of parathyroid administration; also Austin and Matthews [1927] found a similar effect and prefer to explain their results on a dehydration basis rather than as a direct action of the hormone on the tissue cells. Merrit and Bauer [1930] found no consistent changes in the calcium content of the cerebro-spinal fluid or aqueous humour following increased serum calcium as a result of parathyroid administration. Pugsley and Selye [1933] have shown that the increased serum calcium and increased calcium excretion in the rat following parathyroid administration can be accounted for by a direct action on the bone cells. SUMMARY. 1. The saliva secreted by the parotid gland of the dog by means of meat powder, sodium chloride or hydrochloric acid was found to have a calcium concentration of over three times the serum calcium, while the saliva secreted by means of pilocarpine hydrochloride (0.3 mg./kg.) stimulation had a lower concentration of calcium than that stimulated by the other methods. 2. An increased serum calcium brought about by parathyroid hormone or irradiated ergosterol was accompanied by an increase in the saliva calcium which exceeded the rise in the serum calcium

5 100 L. ANDREYEV AND L. I. PUGSLEY. 3. The rise in saliva calcium following parathyroid hormone administration offers a means of measuring the potency of parathyroid gland extracts, where the taking of blood presents certain difficulties. The authors are deeply indebted to Prof. B. P. Babkin and Prof. J. B. Collip for much helpful criticism and advice throughout the course of this work. REFERENCES. Austin, W. C. and Matthews, S. A. (1927). Amer. J. Phy8iol. 81, 552. Baxter, H. (1932). Arch. int. Pharmacodyn. 42, 411. Baxter, H. (1933). J. biol. Chem. (in the Press). Bunting, R. W. and Wixon, F. H. (1917). J. Nat. Dent. A88oc. 4, 81. Clark, E. P. and Collip, J. B. (1925). J. biol. Chem. 63, 461. Clark, G. W. and Shell, J. S. (1927). Dental Co8mo8, 69, 500, 605. De Beer, E. J. and Wilson, D. N. (1932). Ibid. 95, 671. Hubbel, R. B. and Bunting, R. W. (1932). J. Nutrition, 5, 599. Krasnov, F., Karshan, M. and Krejci, L. E. (1932). J. Lab. clin. Med. 17, Merrit, H. H. and Bauer, W. (1930). J. biol. Chem. 90, 233. Parhon, C. I. and Cahane, M. (1932). C. R. Soc. Biol., Paris, 109, 243. Pugsley, L. I. and Selye, H. (1933). J. Physiol. 79, 113. Werther, H. (1886). Pflulqers Arch. 38, 293.