PLASMA INSULIN AND GROWTH HORMONE IN DAIRY COWS; DIURNAL VARIATION AND RELATION TO FOOD INTAKE AND PLASMA SUGAR AND ACETOACETATE LEVELS

1973 ◽  
Vol 73 (2) ◽  
pp. 289-303 ◽  
Author(s):  
Knut Hove ◽  
Anne Kristine Blom

ABSTRACT Marked diurnal variations were found in plasma growth hormone (GH), insulin, acetoacetate (AcAc) and sugar in two herds (U and A) of dairy cows kept at two different levels of feeding. Seven animals from each herd were tested. The main diurnal variations were related to food intake, a significant increase in plasma insulin, and a significant decrease in plasma sugar being found. The acetoacetate level rose significantly during feeding in herd U (moderately underfed), while no significant increase was found in herd A (adequately fed). Plasma growth hormone was found to decrease (P < 0.01) only during feeding in herd U, while no change in the GH level could be detected in herd A. The mean level of GH in herd U was found to be twice the value found in herd A. There were no significant differences between the herds in plasma insulin and sugar. Significant differences in plasma levels of GH, insulin and sugar were found between animals when analysed within the herds. Variations in the levels of insulin and acetoacetate were very small during the night. This is contrary to GH, which shows the least variation during food intake. The correlation coefficient between the plasma components was low, although in many cases significant.

1976 ◽  
Vol 82 (4) ◽  
pp. 758-766 ◽  
Author(s):  
Anne Kristine Blom ◽  
K. Halse ◽  
K. Hove

ABSTRACT Plasma growth hormone (GH) of eight young, sexually mature, pedigree bulls, observed at hourly intervals, varied during the day in a manner indicating intermittent secretion in peaks or bursts. The diurnal GH averages were about 10 ng/ml. GH averages for 2–3 h intervals showed minima following or during the periods of morning and afternoon feeding. A third minimum occurred between 10 and 12 p.m. Peak activity, estimated by the frequency of GH values greater than 10 ng/ml was significantly reduced during two of these low-GH-periods (afternoon and late night). The minima in GH followed after (morning) or coincided with (afternoon) maxima in plasma insulin (two materials, GH/insulin, 11 a. m.-10 p. m.: r=−0.31 and −0.34, P < 0.01). This means that the two hormones behaved after food intake much in the same ways as in man in spite of the fact that plasma sugar decreased after feeding (GH/sugar, 11 a. m.-10 p.m.: r = 0.27, two materials combined, P < 0.001). The possibility of GH involvement in the hour-to-hour metabolic homoeostasis of the animals is discussed.


1971 ◽  
Vol 66 (4) ◽  
pp. 577-586 ◽  
Author(s):  
R. C. Turner ◽  
B. Schneeloch ◽  
P. Paterson

ABSTRACT Plasma immunoreactive insulin and growth hormone of 20–24 weeks' gestation human foetuses were assayed in serial samples following delivery by hysterotomy. The mean umbilical cord plasma growth hormone concentration was 71 ng/ml (range 13–120 ng/ml) and the mean plasma insulin was 5 μU/ml (range 2–8 μU/ml). Following delivery the growth hormone levels increased, but there was no significant change in plasma insulin concentration. The hypothalamic-hypophyseal axis controlling growth hormone secretion appears to be developed by 20 weeks' gestation, and »stress« appears to be a provocative stimulus.


BMJ ◽  
1974 ◽  
Vol 1 (5906) ◽  
pp. 485-488 ◽  
Author(s):  
P. Z. Zimmet ◽  
J. R. Wall ◽  
R. Rome ◽  
L. Stimmler ◽  
R. J. Jarrett

1994 ◽  
Vol 78 (1) ◽  
pp. 215-226 ◽  
Author(s):  
Harry S. Koelega

At least a dozen studies have investigated the effects of food intake on olfactory sensitivity. Most studies reported the existence of food-related changes in sensitivity but the findings are highly discrepant. In the present study, earlier studies are reviewed, their shortcomings discussed, and the results of an experiment are reported. Using an air-dilution olfactometer, sensitivity to the odor of acetophenone was assessed throughout the day in seven subjects on four consecutive days, both with and without lunch. In the group data no consistent pattern of changes in sensitivity related to food intake was found, although some individual subjects showed a diurnal variation. Some suggestions are made enhancing the possibility that in the future a relationship between food intake and olfactory sensitivity may be observed.


PEDIATRICS ◽  
1973 ◽  
Vol 52 (1) ◽  
pp. 75-82
Author(s):  
Rosita S. Pildes ◽  
Daksha A. Patel ◽  
Menachem Nitzan

The present study was undertaken to determine the rate of glucose disposal in the pathogenesis of symptomatic neonatal hypoglycemia. Intravenous glucose (1 gm/kg) was injected rapidly into 11 hypoglycemic and eight control newborn infants. The percentage (mean ± SEM) disappearance rate per minute (Kt) was significantly higher (p &lt; 0.001) in the hypoglycemic newborn infants compared with that of the controls (2.8 ± 0.1 versus 1.2 ± 0.1, respectively). Baseline plasma insulin concentrations were significantly higher (p &lt; 0.01) in the hypoglycemic (16.8 ± 3.9µU/ml) than those of the controls (3.5 ± 1.0µU/ml). Baseline plasma growth hormone values in the hypoglycemic newborns were 16.6 ± 5.7 mµg/ml. Growth hormorne values rose in the hypoglycemic to 36 ± 10 mµg/ml at 10 minutes and to 64 ± 13 mµg/ml by 60 minutes.


1986 ◽  
Vol 66 (4) ◽  
pp. 995-1001
Author(s):  
G. J. MEARS

Plasma concentrations of growth hormone (GH) and insulin were monitored in 11 chronically cannulated ovine fetuses and their mothers during the last month of gestation to obtain information on the role that these hormones have in determining fetal growth rate. Maternal plasma GH and insulin concentrations were independent of stage of gestation and lamb birth weights. Fetal plasma insulin concentrations were episodic in nature, independent of stage of gestation, and tended to be higher in fetuses that were heavier at birth. Fetal plasma GH concentrations were only slightly episodic in nature, were tenfold higher than maternal levels at 116–124 d gestation and increased by approximately another 25% prior to parturition. Fetal plasma GH concentrations were negtively correlated with lamb birth weights. In twin preparations, fetal plasma GH concentrations were significantly lower in the twin that was heaviest at birth. The lower GH concentrations found in faster growing fetuses are suggestive of a more rapid metabolic clearance of GH by the tissues of these animals. The results indicate that circulating fetal GH and, possibly, insulin are involved in determining the rate of ovine-fetal growth. Key words: Ovine birth weights, fetal GH, fetal insulin, fetal growth


1976 ◽  
Vol 83 (1) ◽  
pp. 15-25
Author(s):  
M. Vanderschueren-Lodeweyckx ◽  
W. Proesmans ◽  
E. Eggermont ◽  
R. Eeckels

ABSTRACT The effects of the infusion in four different dosages (0.001, 0.005, 0.02 and 0.2 mg/kg/min during 60 min) of cyclic 3′,5′-adenosine monophosphate and of its dibutyryl derivative on plasma growth hormone and on glucose, immunoreactive insulin and cortisol were studied in 38 normal subjects and in 10 patients with idiopathic hypopituitarism. In normal subjects cyclic 3′,5′-adenosine monophosphate provokes an increase in plasma growth hormone levels (only when a dosage of 0.2 mg/kg/min is used) without any changes in plasma glucose, insulin and cortisol. The maximal value of the means is observed 75 min after starting the infusion. Dibutyryl cyclic 3′,5′-adenosine monophosphate (0.2 and 0.02 mg/kg/min) provokes a dose-related rise in plasma growth hormone levels which is always preceded by hyperglycaemia and hyperinsulinaemia. The peak of the mean growth hormone levels occurs at 135 min after initiation of the infusion. In all but one hypopituitary patients the nucleotides do not promote growth hormone secretion. It is concluded that exogenous cyclic 3′,5′-adenosine monophosphate and its dibutyryl derivative may not be considered as analogous and that both compounds may contribute to study growth hormone release in normal subjects and in patients with growth abnormalities.


1976 ◽  
Vol 82 (2) ◽  
pp. 544-552 ◽  
Author(s):  
Knut Hove ◽  
Anne Kristine Blom

ABSTRACT Two or three foetal lambs regularly result in a varying degree of carbohydrate shortage in mother ewes in late pregnancy. We have investigated the correlation between plasma insulin, growth hormone and energy substrate concentrations in ewes 8 and 1 weeks before lambing. Plasma growth hormone was fairly constant (2–3 ng/ml) throughout the 24-h cycle 8 weeks before parturition. Seven weeks later higher average levels and increased diurnal fluctuations were observed in 3 out of 4 multiparous ewes. The average post-absorptive insulin levels were reduced by 50 per cent during the same interval. Simultaneously decreased post-absorptive sugar and increased acetoacetate levels were observed. It is concluded that the hormonal adaptations to the increasing carbohydrate deficit in late pregnancy, especially among multiparous ewes, include: a) reduced post-absorptive plasma insulin levels, b) reduced insulin responses to feeding, and c) increased levels of growth hormone in the plasma.


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