GONADOTROPHIN RESPONSES TO GnRH PULSES IN HYPOGONADOTROPHIC HYPOGONADISM: LH RESPONSIVENESS IS MAINTAINED IN THE PRESENCE OF LUTEAL PHASE CONCENTRATIONS OF OESTROGEN AND PROGESTERONE

LH pulse secretion changes during the menstrual cycle from a rapid regular pattern in the follicular phase to a slower and irregular pattern in the luteal phase. To determine whether the irregular LH pulse pattern in the luteal phase reflects altered GnRH secretion or altered pituitary responsiveness to GnRH, we gave low dose GnRH pulses (25 ng/kg i.v.) every 2 h or every hour for 10 or 12 d to three women with isolated GnRH deficiency. After 4 d of GnRH alone, oestradiol (E 2 ) was given and after 6 d progesterone (P) was added to mimic the hormonal milieu of the luteal phase. LH and FSH were measured every 4 h throughout and also every 20 min for 6 or 12 h, before and after GnRH alone (day 0 and day 4), after E 2 (day 6), and after E 2 + P (day 10 and day 12). Both GnRH pulse frequencies resulted in a rapid increase in plasma FSH to peaks on day 4 (every 2 h) and day 2 and 3 (every hour). FSH concentrations then declined as plasma E 2 rose to 50–80 pg/ml reflecting the selective inhibitory effect of E 2 on FSH release. Plasma LH was also increased after the hourly GnRH injections and this regimen was associated with a more rapid rise in E 2 reflecting follicular maturation. In contrast to the differences in mean hormone concentrations, administration of GnRH at both frequencies resulted in sustained one-on-one responsiveness of LH that was maintained in the presence of both oestrogen and progesterone at mid-luteal phase concentrations. We conclude that the slow frequency of LH pulses observed during the luteal phase reflects decreased GnRH pulse frequency rather than impaired pituitary responsiveness to GnRH.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74947/1/j.1365-2265.1987.tb00786.x.pd

EFFECT OF CORTISOL TREATMENT ON HORMONAL RELATIONSHIPS IN CONGENITAL ADRENAL HYPERPLASIA

The temporal relationship between administration of cortisol and serum 17Α-hydroxyprogesterone was investigated in five patients aged 9-19 years with congenital adrenal hyperplasia due to 21-hydroxylase deficiency. There was marked variability in the 17Α-hydroxyprogesterone response (determined hourly for 24 h) of individual patients to administration of cortisol. Mean concentration was less than 0.030 Μmol/l in one patient but 0.519Μ mol/l in another. Levels were higher in all patients while off treatment, and were greatest in those with salt-losing adrenal hyperplasia. Growth hormone secretion was not suppressed by treatment with cortisol. Withdrawal of cortisol for 3 days resulted in a significant decrease in the mean serum FSH/LH ratio and a rise in serum testosterone in all subjects. Episodic release of gonadotrophins persisted in the adolescent patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75713/1/j.1365-2265.1977.tb02002.x.pd

Botulismo em ruminantes causado pela ingestão de cama-de-frango Botulism in ruminants being fed with poultry litter

Botulismo é uma intoxicação causada pela ingestão das toxinas produzidas pelo Clostridium botulinum, que acomete mamíferos e aves. Neste trabalho é descrito um surto de botulismo em ruminantes, ocorrido em duas propriedades localizadas no município de Patos, no Estado da Paraíba, Brasil. Em uma das propriedades, de um total de 88 bovinos, 85 (96,6%) vieram a óbito. Na segunda, morreram 145 ovinos (96,7%), 233 caprinos (57,8%) e 30 bovinos (96,8%). Os animais acometidos apresentavam paralisia progressiva, dificuldade de locomoção, sialorréia e dispnéia. A morte ocorreu entre 24 e 48 horas após o início dos sinais, por parada cardio-respiratória. Nenhuma alteração significativa foi observada no exame post-mortem. O diagnóstico de botulismo foi confirmado pela demonstração das toxinas C e D no conteúdo intestinal e na cama-de-frango utilizada na alimentação dos animais, pela técnica de soroneutralização em camundongos.<br>Botulism is a poisoning caused by the ingestion of toxins produced by Clostridium botulinum, that infects mammals and birds. This article reports an outbreak of botulism in two different flocks of ruminants at Paraíba, Brazil. In one, 85 out of 88 (96.6%) cattles died. In the other, 145 (96.7%) sheeps, 233 (57.8%) goats and 30 (96.8%) cattles died. Clinical signs were progressive paralysis, difficulties in moving, sialorrhoe and dyspnoe. Death occurred 24 to 48 hours after the beginning of clinic signs and at post-mortem examination no noteable changes were observed. Type C and D toxins were demonstrated in the intestinal contents and poultry litter by neutralization test in mice