Transsphenoidal pituitary surgery was performed in 64 patients with Cushing's disease in search of a corticotroph adenoma. In 4 patients, profuse local bleeding prevented completion of the exploration. Of the 60 patients who had an adequate exploration, 4 could not be followed after surgery. Short term assessment of the surgical outcome (3-6 months postoperatively) was performed on 60 patients, including the 4 who had incomplete pituitary exploration. Forty-two patients (70%) were judged as immediate successes [urinary cortisol excretion, less than 90 micrograms (less than 248 nmol)/day]; the mean urinary cortisol excretion and plasma ACTH level fell from 463 +/- 70 (+/- SE) to 26.7 +/- 3.6 micrograms/day (1277 +/- 193 to 74 +/- 10 nmol/day; n = 33) and from 111 +/- 33 to 36 +/- 14 pg/mL (24 +/- 7 to 8 +/- 3 pmol/L; n = 23) in patients who had both measurements pre- and postoperatively. Eighteen patients (30%) were judged as immediate failures; neither urinary cortisol excretion nor plasma ACTH levels changed significantly in patients who had both measurements pre- and postoperatively. The preoperative epidemiological, clinical, hormonal, and radiological characteristics of the 2 groups were similar. Histological examination of pituitary fragments removed in 58 of the 60 patients evaluated postoperatively revealed the presence of tumoral tissue in a higher percentage of patients in the immediate success group (72%) than in the immediate failure group (24%; P less than 0.01). The 42 patients in the immediate success group were followed from 6 months to 7 yr (median, 2 yr); 6 patients had recurrences from 2-3 yr after operation. Actuarial analysis indicates that the probability of a patient remaining well 6 yr after surgery is 72 +/- 20% (95% confidence limit). Most of the patients in the immediate success group had transient ACTH deficiency preceding a progressive return to normal pituitary-adrenal function.

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(6A0727). trope, thyrotrope, and corticotrepe cells but were very scarce in prolactin cells and absent in somatotrope cells. In features or by immunodetection of its hormone content. These findings suggest that laminin might be synthesized and exported by all the glandular anterior pituitary cells, according to different pathways. Materials and Methods Materials Antibodies. Affinity-purified goat antibodies to laminin (a.laminin)

Dendritic synthesis and release of neuropeptides have been demonstrated in hypothalamic neurosecretory neurons. Here we tested whether this mechanism may be applicable to galanin in rat locus coeruleus (LC) neurons. Light and electron microscopic immunocytochemistry demonstrated the occurrence of galanin peptide in secretory granules within dendritic processes. In situ hybridization at the light and electron microscopic level showed galanin mRNA in these LC processes. Moreover, the levels of the transcript and its extension into the dendrites were significantly increased by reserpine treatment. Finally, evidence for exocytotic release from large dense-core vesicles in LC dendrites was obtained by using tannic acid-treated slices. Taken together, these results indicate that galanin can be synthesized in, and possibly released from, LC. These data support a key function of the neuropeptide galanin as an auto-paracrine local modulator in a major, strongly divergent monoaminergic regulatory system.

SUMMARYIn addition to the circulating renin-angiotensin system (RAS), a local system has been postulated in the anterior pituitary because immunodetection of its components in various mammalian species. However, different cell types appear to be involved in different species, and there is no general consensus on the subcellular localization of prorenin, renin and angiotensinogen. In this ultrastructural study, we investigated and quantified the presence of these components using double or triple immunogold labeling methods, in all the immunologically identified glandular cell types of the rat anterior pituitary. In contrast to previous reports, all these components were identified not only in lactotropes and gonadotropes but also in somatotropes, corticotropes, and thyrotropes. The highest levels were detected in lactotropes and gonadotropes, and renin gave the greatest signal. Angiotensinogen, prorenin, and renin were co-localized in the secretory granules of all rat pituitary glandular cell types. The simultaneous detection of the substrate (angiotensinogen) and both its specific cleavage enzyme and its proenzyme within the same granule suggests intragranular processing of this component. Moreover, the localization of these three constituents in the secretory granules also suggests that, in the rat anterior pituitary, they follow the regulated secretory pathway. (J Histochem Cytochem 46:301-311, 1998)

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Laminin (LAM), a glycoprotein component of basement membranes, has been previously detected within several subcellular compartments of prolactin (PRL) cells in the pituitary gland. The present work was aimed at comparing the subcellular localization of PRL, a specific secretory product, with that of LAM, in relation to the secretory activity of PRL cells. LAM and PRL were located in parallel, by ultrastructural immunocytochemistry, in PRL cells of lactating female Wistar rats, either stimulated by suckling, or blocked by weaning, or reactivated by suckle following short-term weaning. Variations in physiological conditions were correlated with a redistribution of PRL immunoreactivity within morphologically modified compartments. The Golgi apparatus became hypertrophied, and PRL impressively accumulated within saccules of the Golgi stacks of blocked cells. On the contrary, no apparent changes occurred in LAM distribution, at least at the Golgi level. Only a slight increase of LAM immunoreactivity was observed in rough endoplasmic reticulum after a long weaning period. PRL could be detected in most of the secretory granules and particularly in forming elements, whereas LAM was observable at the peripheral edge of some mature granules. Such a labeling was not markedly influenced by the physiological state. The prominent structures, indicative of crinophagic activity, characteristic of blocked cells, contained masses of dense material, which were always immunopositive with antibodies to PRL, but never to LAM. These observations could suggest that, in PRL cells, intracellular transport and exportation of LAM are controlled by mechanisms independent from those involved in the regulation of PRL secretion.