INHIBITION OF ADRENOCORTICAL F U N C T I O N BY I N T R A V E N O U S ADMINISTRATION OF S O D I U M P E N T O B A R B I T A L IN C O C K S B Y I. Nm, D. YAM AND M. PEREK
Department of Animal Science, Faculty of Agriculture, The Hebrew University of Jerusalem, Israel
Rehovot,
(Received for publication August 1, 1975)
ABSTRACT The response of awake and anesthesized cocks with sodium pentobarbital to stressful stimuli has been examined. The stressful stimuli was immersion in cold water. In the awake cocks plasma corticosterone concentration was increased about 4 fold; they started shivering shortly after immersion and recovered after cessation of the treatment. In the anesthesized ones there was no increase in plasma corticosterone concentration, they did not shiver and died shortly after immersion. POULTRY SCIENCE 55: 450-451, 1976
MMERSION in cold water was shown to be a powerful stressful stimuli causing an immediate increase in the blood plasma concentration of corticosterone in chicks (Nir et al., 1975). The inhibitory effect of sodium pentobarbital on the chicken hypothalamus was demonstrated by Snapir et al. (1973), who administered sodium pentobarbital through a canula implanted in the ventromedial area of cock's hypothalamus. This treatment affected the hypothalamus dependent control on feed intake. The objective of the present work was to study the effect of I.V. administration of sodium pentobarbital on the adrenocortical function of cockerels immersed in cold water. MATERIALS AND METHODS Ten adult cross-bred New Hampshire x White Leghorn cocks were used. Five were anesthesized before immersion in cold water (21° C.) by an I.V. injection of 0.6 ml. sodium pentobarbital (Sombital 6% diluted in 10% ethanol, 20% propylen glycol and 64% bidistilled water; Rafa, Israel). Five cocks (controls) were immersed with no previous treatment. One ml. blood was drawn from the wing vein with an heparinized syringe before and 1, 5, 10, 20 and 30 minutes following immersion. The blood was centrifuged and the plasma kept at —22° C. for the determi-
nation of corticosterone. The corticosterone concentration in the blood plasma was determined by the competitive protein binding radioassay according to Murphy (1967) as described by Nir et al. (1975). After immersion the cocks were placed in an incubator (36° C.)for recovery. Rectal temperature was recorded before and during immersion with a mercury thermometer. RESULTS AND DISCUSSION Immersion in cold water caused an immediate drop in body temperature (from 41.6° C. before to 32° C. following 30 minutes). No difference was observed in this respect between the anesthesized and the control cocks (Table 1). The blood plasma corticosterone level increased up to about 4 fold in all the control cocks; it did not increase in the treated ones (Table 1). All the control birds shivered following 3-5 minutes immersion and recovered after a short stay in the incubator. In opposition no shivering was noted in the treated ones who died shortly after the cold treatment. These findings indicate that anesthesia with sodium pentobarbital inhibits the adrenocortical function, and emphasizes the importance of the adrenocortical integrity when coping with a strong stressful stimuli. Adrenal dependence on the integrity of the hypothalamus was demonstrated when 450
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TABLE 1.—Blood plasma corticosterone and body temperature of control (awake) and anesthesized cocks with sodium pentobarbital before and following immersion in cold water (21° C.) Mean ± SEM Body temperature Plasma corticosterone C.° ng ./ml Time Anesthesized Anesthesized Control Control minutes 41.6 ± 0.2 112 ± 5 126 ± 16 0 41.6 ± 0 . 1 41.4 ± 0.3 41.5 ± 0.2 114 ± 6 288 ± 4 4 1 38.2 ± 0.4 38.4 ± 0.3 116 ± 7 310 ± 47 5 36.0 ± 0.4 36.1 ± 0.3 116 ± 15 336 ± 57 10 34.1 ± 0 . 5 34.3 ± 0.4 128 ± 9 414 ± 49 20 32.3 ± 0.2 32.6 ± 0.3 132 ± 10 473 ± 45 30 All the differences in blood plasma corticosterone between the control and the anesthesized cocks (except 0 time) are statistically significant P < 0.001. Differences in body temperature are not statistically significant.
REFERENCES Bryant, B., 1966. Urinary 17-hydroxysteroid excretion in guinea pigs with hypothalamic lesions. Acta Endoricologica, 53: 369-381. Frankel, A. I., J. W. Graber and A. V. Nalbandov, 1967. The effect of hypothalamic lesions on adrenal
functions in intact and adenohypophysectomized cockerels. Gen. Comp. Endocrinol 8: 387-396. Murphy, E. B. 1967. Some studies on the protein binding of steroids and their application to the routine micro and ultramicro measurement of various steroids in body fluids by competitive protein binding radioassay. J. Clin. Endocr. Metab. 27: 973-990. Nir, I., D. Yam and M. Perek, 1975. Effects of stress on the corticosterone content of the blood plasma and adrenal gland of intact and bursectomized Gallus Domesticus. Poultry Sci. 54: 2101-2110. Salem, M. H., H. W. Norton and A. V. Nalbandov 1970. A study of ACTH and CRF in chickens. Gen. Comp. Endocrinol. 14: 270-280. Snapir, N., B. Robinzon, M. Goldshalk, E. D. Heller and M. Perek 1973. The effect of intrahypothalamic administration of sodium pentobarbital on eating behaviour and feed intake in chickens. Physiol. Behavior, 19: 97-100.
NEWS AND NOTES (Continued from page 449) academic institutions, and other organizations. For further information, contact Richard Sweet, Product Manager, Data Base Services, Institute for Scientific Information, 325 Chestnut Street, Philadelphia, Pennsylvania, 19106. The Institute for Scientific Information (I.S.I.) has created a new position—Lecturer-Professional Education—designed to help academic institutions enhance their instructional programs on the use of scientific and technical information. Starting in 1976, I.S.I, will offer without charge
a professional reference librarian /educator to serve as a guest lecturer, seminar leader, or panelist who will provide instruction on the role the company's services play in information retrieval for the sciences and the social sciences. Participation by the I.S.I. lecturer will be by invitation from the schools and presentations will be tailored to meet the needs of graduate or undergraduate students. I.S.I, sees two major sources of demand for its new program. One is library and information science schools which can use the lecturer to provide special-
(Continued on page 453)
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hypothalamic lesions resulted in decreased steroidogenesis (Frankel, 1967). A corticotrophin releasing factor has been characterized in crude extracts of the hypothalamus (Salem et al., 1970). Guinea pigs with hypothalamic bilateral lesions displayed a significant reduction in 17 hydroxycorticosteroid excretion when exposed to cold. It is suggested that I.V. administration of sodium pentobarbital affected the adrenocortical function by its inhibitory effect on the hypothalamus.
Department of Animal Science, Faculty of Agriculture, The Hebrew University of Jerusalem, Israel
Rehovot,
(Received for publication August 1, 1975)
ABSTRACT The response of awake and anesthesized cocks with sodium pentobarbital to stressful stimuli has been examined. The stressful stimuli was immersion in cold water. In the awake cocks plasma corticosterone concentration was increased about 4 fold; they started shivering shortly after immersion and recovered after cessation of the treatment. In the anesthesized ones there was no increase in plasma corticosterone concentration, they did not shiver and died shortly after immersion. POULTRY SCIENCE 55: 450-451, 1976
MMERSION in cold water was shown to be a powerful stressful stimuli causing an immediate increase in the blood plasma concentration of corticosterone in chicks (Nir et al., 1975). The inhibitory effect of sodium pentobarbital on the chicken hypothalamus was demonstrated by Snapir et al. (1973), who administered sodium pentobarbital through a canula implanted in the ventromedial area of cock's hypothalamus. This treatment affected the hypothalamus dependent control on feed intake. The objective of the present work was to study the effect of I.V. administration of sodium pentobarbital on the adrenocortical function of cockerels immersed in cold water. MATERIALS AND METHODS Ten adult cross-bred New Hampshire x White Leghorn cocks were used. Five were anesthesized before immersion in cold water (21° C.) by an I.V. injection of 0.6 ml. sodium pentobarbital (Sombital 6% diluted in 10% ethanol, 20% propylen glycol and 64% bidistilled water; Rafa, Israel). Five cocks (controls) were immersed with no previous treatment. One ml. blood was drawn from the wing vein with an heparinized syringe before and 1, 5, 10, 20 and 30 minutes following immersion. The blood was centrifuged and the plasma kept at —22° C. for the determi-
nation of corticosterone. The corticosterone concentration in the blood plasma was determined by the competitive protein binding radioassay according to Murphy (1967) as described by Nir et al. (1975). After immersion the cocks were placed in an incubator (36° C.)for recovery. Rectal temperature was recorded before and during immersion with a mercury thermometer. RESULTS AND DISCUSSION Immersion in cold water caused an immediate drop in body temperature (from 41.6° C. before to 32° C. following 30 minutes). No difference was observed in this respect between the anesthesized and the control cocks (Table 1). The blood plasma corticosterone level increased up to about 4 fold in all the control cocks; it did not increase in the treated ones (Table 1). All the control birds shivered following 3-5 minutes immersion and recovered after a short stay in the incubator. In opposition no shivering was noted in the treated ones who died shortly after the cold treatment. These findings indicate that anesthesia with sodium pentobarbital inhibits the adrenocortical function, and emphasizes the importance of the adrenocortical integrity when coping with a strong stressful stimuli. Adrenal dependence on the integrity of the hypothalamus was demonstrated when 450
Downloaded from http://ps.oxfordjournals.org/ by guest on April 12, 2015
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TABLE 1.—Blood plasma corticosterone and body temperature of control (awake) and anesthesized cocks with sodium pentobarbital before and following immersion in cold water (21° C.) Mean ± SEM Body temperature Plasma corticosterone C.° ng ./ml Time Anesthesized Anesthesized Control Control minutes 41.6 ± 0.2 112 ± 5 126 ± 16 0 41.6 ± 0 . 1 41.4 ± 0.3 41.5 ± 0.2 114 ± 6 288 ± 4 4 1 38.2 ± 0.4 38.4 ± 0.3 116 ± 7 310 ± 47 5 36.0 ± 0.4 36.1 ± 0.3 116 ± 15 336 ± 57 10 34.1 ± 0 . 5 34.3 ± 0.4 128 ± 9 414 ± 49 20 32.3 ± 0.2 32.6 ± 0.3 132 ± 10 473 ± 45 30 All the differences in blood plasma corticosterone between the control and the anesthesized cocks (except 0 time) are statistically significant P < 0.001. Differences in body temperature are not statistically significant.
REFERENCES Bryant, B., 1966. Urinary 17-hydroxysteroid excretion in guinea pigs with hypothalamic lesions. Acta Endoricologica, 53: 369-381. Frankel, A. I., J. W. Graber and A. V. Nalbandov, 1967. The effect of hypothalamic lesions on adrenal
functions in intact and adenohypophysectomized cockerels. Gen. Comp. Endocrinol 8: 387-396. Murphy, E. B. 1967. Some studies on the protein binding of steroids and their application to the routine micro and ultramicro measurement of various steroids in body fluids by competitive protein binding radioassay. J. Clin. Endocr. Metab. 27: 973-990. Nir, I., D. Yam and M. Perek, 1975. Effects of stress on the corticosterone content of the blood plasma and adrenal gland of intact and bursectomized Gallus Domesticus. Poultry Sci. 54: 2101-2110. Salem, M. H., H. W. Norton and A. V. Nalbandov 1970. A study of ACTH and CRF in chickens. Gen. Comp. Endocrinol. 14: 270-280. Snapir, N., B. Robinzon, M. Goldshalk, E. D. Heller and M. Perek 1973. The effect of intrahypothalamic administration of sodium pentobarbital on eating behaviour and feed intake in chickens. Physiol. Behavior, 19: 97-100.
NEWS AND NOTES (Continued from page 449) academic institutions, and other organizations. For further information, contact Richard Sweet, Product Manager, Data Base Services, Institute for Scientific Information, 325 Chestnut Street, Philadelphia, Pennsylvania, 19106. The Institute for Scientific Information (I.S.I.) has created a new position—Lecturer-Professional Education—designed to help academic institutions enhance their instructional programs on the use of scientific and technical information. Starting in 1976, I.S.I, will offer without charge
a professional reference librarian /educator to serve as a guest lecturer, seminar leader, or panelist who will provide instruction on the role the company's services play in information retrieval for the sciences and the social sciences. Participation by the I.S.I. lecturer will be by invitation from the schools and presentations will be tailored to meet the needs of graduate or undergraduate students. I.S.I, sees two major sources of demand for its new program. One is library and information science schools which can use the lecturer to provide special-
(Continued on page 453)
Downloaded from http://ps.oxfordjournals.org/ by guest on April 12, 2015
hypothalamic lesions resulted in decreased steroidogenesis (Frankel, 1967). A corticotrophin releasing factor has been characterized in crude extracts of the hypothalamus (Salem et al., 1970). Guinea pigs with hypothalamic bilateral lesions displayed a significant reduction in 17 hydroxycorticosteroid excretion when exposed to cold. It is suggested that I.V. administration of sodium pentobarbital affected the adrenocortical function by its inhibitory effect on the hypothalamus.
