Markku Hyyppä

A histochemical study of the primary catecholamines in the hypothalamic neurons of the rat in relation to the ontogenetic and sexual differentiation

SummaryThe alterations in the content of the primary catecholamines in the hypothalamus have been studied with the histochemical technique of para-formaldehyde induced fluorescence.In the adult normal rats, independent of the sex, the fluorescence is located in the cell bodies of a few arcuate neurons, around the perikarya of the arcuate, para-ventricular and supra-optic neurons, and in the nerve endings of the arcuate neurons in the median eminence.The appearance of the primary catecholamines takes place at the 20th day of gestation in the para-ventricular and arcuate-peri-ventricular regions. In the supra-optic nucleus the fluorescent nerve terminals are not seen before birth. In the outer layer of the median eminence the fluorescence develops around the 5th post-natal day. No sexual differences were observed in the maturation of the primary catecholamines during the ontogenic development of the rat.More fluorescent cell bodies and nerve endings are seen in the arcuate neurons during the late diestrus than during estrus. The number and intensity of the catecholamine fluorescent neurons in the arcuate nucleus increases during the pregnancy. Castration increases slightly the number and intensity of the fluorescent cell bodies in the arcuate nucleus, but it diminishes the fluorescence in the median eminence. The changes were compensated by a treatment with testosterone propionate. Hypophysectomy alone has no effect on the fluorescence of the hypothalamic neurons.

Differentiation of the hypothalamic nuclei during ontogenetic development in the rat

SummaryThe ontogenetic development of the hypothalamic nuclei of the rat was examined from the 16th post-coital day to adult age in both sexes, which were determined separately. The following conclusions have been drawn:1.The hypothalamus is visible already before the 16th day of gestation.2.The walls of the third ventricle are first composed of primitive cell layers, from which the migration of neurons proceeds on the 15th or 16th day. At this stage the differentiation of the wall of the third ventricle occurs: the germinal-, mantle-and marginal layers appear.3.The differentiation of the nuclei starts, with some exceptions, before the 19th day of gestation.4.Nn. suprachiasmaticus, supraopticus, periventricularis anterior, arcuatus and one part of paraventricularis differentiate from the lateral border of the germinal layer. Nn. ventromedialis, dorsomedialis, hypothalamicus anterior, praeoptici, praemamillaris ventralis, praemamillaris dorsalis, mamillaris medialis, mamillaris lateralis and the greater part of paraventricullaris differentiate from the mantle layer. Lateral nuclei, of which only nucleus tuberomamillarius has been described, differentiate from the marginal layer.5.Some nuclei which belong to the hypothalamo-hypophyseal area have a peak in their differentiation during the critical period when the function of the hypothalamo-hypophyseal axis also starts.6.It is stated that the development of the nuclei in the rat hypothalamus compared to that of the other mammals is similar only to that of the mouse. It takes place quite slowly before and after birth.7.Sexual differences are not to be seen in the development of the nuclei.

Levotryptophan treatment in migraine.

SYNOPSIS

Transient Effect of L-Tryptophan in Progressive Myoclonus Epilepsy Without Lafora Bodies: Clinical and Electrophysiological Study

Summary: A double‐blind crossover trial with 2 g L‐tryptophan ‐and placebo was carried out with five familial and two sporadic patients with progressive myoclonus epilepsy (PME) without Lafora bodies. L‐Tryptophan improved the clinical condition in six out of seven patients. Clinical improvement in ambulation, myoclonic jerks, and general condition was most evident. The change was statistically significant. In visual assessment of EEGs, the amount of paroxysmal activity and dysrhythmia of the background activity decreased in six out of seven patients on L‐tryptophan. The quantitative EEG revealed a decrease in the power bands of theta, alpha, and beta activity in five of six patients on the second day of L‐tryptophan treatment. In familial PME cases, the responses were consistently beneficial. With long‐term L‐tryptophan therapy, the effect disappeared or was even reversed in three of seven patients after 3 to 4 weeks. These findings indicate that therapy with serotonin precursors is worthy of further trial in PME and that deficient tryptophan metabolism may play a part in the etiology of PME without Lafora bodies.

l-Tryptophan treatment and the episodic secretion of pituitary hormones and cortisol

Abstract (1) l -Tryptophan, the natural precursor of brain serotonin, was administered to healthy subjects. Plasma free and total tryptophan, somatotropin (growth hormone, GH), follitropin (FSH), lutropin (LH), prolactin and cortisol were analysed after the oral administration of 2 g and 100 mg/kg of l -tryptophan or after 1·28 g of l -leucine, at 08:30 and 11:30. (2) Plasma levels of free and total tryptophan were markedly increased after the oral administration of l -tryptophan. (3) Plasma somatotropin levels were significantly elevated after l -tryptophan treatment at different times of day, but this elevation was not dose-dependent. (4) l -Tryptophan or l -leucine treatment did not affect the pulsatile secretion of follitropin and lutropin. (5) Plasma prolactin was not significantly elevated after the oral administration of l -tryptophan. (6) The morning decline of plasma cortisol was significant with or without l -tryptophan. However, no decline was noticed after l -tryptophan in the middle of day.

HISTOCHEMICAL DEMONSTRATION OF CARBONIC ANHYDRASE ACTIVITY IN THE ALIMENTARY CANAL

SummaryCarbonic anhydrase (CAH) activity was histochemically demonstrated in various parts of the alimentary canal of rat and in the stomach of man using the method of Waldeyer and Häusler (1959). The most intense histochemical reaction was observed in the parietal cells of the rat stomach, and reactions of decreasing intensity in the epithelial cells of the colon, appendix, jejunoileum, duodenum and oesophagus in the order mentioned. An intense reaction was also observed in the parietal cells of the stomach of man and a weak activity in the pyloric glands. After electrophoresis on cellulose acetate film the CAH activity in human and rat stomach mucosa showed one band with the same migration rate as the fastest moving band of the erythrocyte CAH.

Plasma pituitary hormones in patients with Parkinson's disease treated with bromocriptine

Bromocriptine was used as a treatment for Parkinsons disease in 15 patients for 20 weeks. Immunoreactive plasma lutrophin (LH), follitrophin (FSH), prolactin, and somatotrophin (GH, growth hormone) concentrations were analysed before and during the treatment. Plasma prolactin levels were very markedly reduced during treatment. Plasma lutrophin levels were increased statistically significantly in female patients, but not in male patients. No changes were noticed in follitrophin levels, but plasma somatotrophin levels were reduced during treatment. No correlations were found between the degree of clinical response and changes in plasma gonadotrophin and somatotrophin. This suggests that the effects of bromocriptine on extrapyramidal and neuroendocrine dopaminergic neurons are unrelated. We suggest careful and frequent controls of neuroendocrine secretion patterns in patients with Parkinsons disease who are treated with high doses of dopamine receptor stimulators, since the responses of some pituitary hormones to bromocriptine are very marked.

L-tryptophan and neuroendocrine regulation in neurologic patients: hormone responses to L-tryptophan loading in patients with hypothalamic lesions.

Abstract 1. Oral administration of 2 g of l -tryptophan induced a marked plasma elevation of total and free tryptophan during the 2 hr of sampling in both normal subjects and in neurologic patients. Plasma free trytophan concentration showed a peak about 60 min after loading with l -tryptophan. 2. Plasma immunoreactive follitrophin (FSH) and lutrophin (LH) levels were not altered after l -tryptophan treatment. 3. Plasma immunoreactive somatotrophin (growth hormone, GH) levels showed a statistically significant elevation after l -tryptophan loading in both normal subjects and in neurologic control patients. In two acromegalic patients there was a very marked elevation of plasma somatotrophin levels 90 min after loading. No responses of plasma somatotrophin to l -tryptophan were observed in patients with hypothalamic lesion or with hypopituitarism. 4. Plasma cortisol levels showed significant morning decline during loading either with l -tryptophan or with l -leucine as placebo in normal subjects and in neurologic control patients. In patients with hypothalamic lesion the monitoring of plasma cortisol concentrations during l -tryptophan loading revealed a primary elevation with a subsequent slight decline. No variation of plasma cortisol was found in patients with hypopituitarism. 5. It was concluded that the brain serotoninergic system can be activated by l -tryptophan treatment which results in alterations of the hypothalamic regulation of somatotrophin secretion. When neuroendocrine dysfunction is due to structural lesions in the hypothalamus or in related regions, l -tryptophan loading is unable to modify somatotrophin secretion. The normal morning decline of plasma cortisol levels is lacking in such patients.

The effects of fixations on Carbonic anhydrase activity

Summary1.The immersion fixation effect of aceton, ethanol, formaldehyde, hydroxyadipaldehyde, glutaraldehyde on the CAH activity of rat liver and kidney cortex has been examined.2.The activity is observed to be preserved best after aceton and hydroxyadipaldehyde fixation.3.The histochemical reaction is most successful, when hydroxyadipaldehyde is used. The other aldehydes are best suited for fixing big blocks.4.The localization of CAH activity is found to be in the luminal surface of the kidney tubule cells, which gives support to the mechanism of urinary acidification presented in literature. Differences in localization with different aldehyde fixations are not observed.

Variation of plasma free tryptophan and CSF 5-HIAA during migraine.

SYNOPSIS