Results are reported in 35 patients with prolactinomas who underwent pituitary surgery within the past five years. After surgery prolactin concentrations became normal in 26 patients and symptoms were alleviated, and nine normal pregnancies were achieved in seven women, including all those who had complained of infertility. Normal prolactin concentrations were restored in 16 of 17 patients with tumours 5-19 mm in diameter but in only six of 11 with tumours <4 mm and four of seven with tumours >20 mm. Normal prolactin concentrations were restored in all those with preoperative concentrations below 1000 mU/l but in none of those with concentrations above 10 000 mU/l. Although not all of the patients were followed up for five years, hyperprolactinaemia did not recur in any patient whose prolactin concentration had returned to normal six weeks after surgery. This included 16 patients with macroprolactinomas (>10 mm in diameter), who were followed up for from two to five years.These data contrast strikingly with those reported by others at similar stages of follow up and show clearly that partial hypophysectomy offers an acceptable alternative treatment for selected patients with prolactinomas. Initial results were encouraging, with claims of success rates of up to 86% for the removal of small tumours and restoration of prolactin concentrations to normal. Despite these promising early results, however, concern about the justification for this approach has grown since Serri et al reported an incidence of recurrence of up to 50% for microadenomas (< 10 mm diameter) and 80% for macroadenomas (>10 mm diameter) five years after transsphenoidal sellotomy and selective removal of prolactinomas.`This concern is highlighted by the availability of effective alternative treatment for such patientsnotably, dopamine agonists, such as bromocriptine, or radiotherapy, or both. " ''We report the results of transethmoidal surgery in 35 patients with prolactinomas. Our results cover five years and emphasise the importance of careful endocrine assessment in the preoperative diagnosis and subsequent management of these patients. Our data are supported by detailed immunohistochemical analyf ' of tumour material removed at surgery.

Pretreatment of normal male volunteers with the cholinergic muscarinic receptor-blocking drug pirenzepine (200 mg p.o.) abolishes the delayed GH response to a meal stimulus. In addition, the glycaemic and insulin responses to meals are significantly reduced following this dose of pirenzepine. The data suggest that the effect of pirenzepine on the glucose response to meals is at least partly independent of the inhibition of GH release. Our findings are of relevance to the further investigation of cholinergic muscarinic antagonist in diabetes mellitus.

To evaluate the ability of gray-scale renal ultrasonography to distinguish cystic neoplasms from benign cysts, 182 cysts or cyst-like masses were reviewed retrospectively by three radiologists with varying degrees of experience in nephrosonography. All cases were proved by needle puncture or surgery. An unequivocal diagnosis of "cyst" based solely on ultrasonography was 98% accurate, with 2% being due to hematomas, localized hydronephrosis, or septa within the cyst. No cystic neoplasms were mistaken for benign cysts. These results indicate that experienced observers using proper technique will rarely be in error in distinguishing non-neoplastic cystic masses from cystic neoplasms by articulated-arm gray-scale ultrasonography, and that routine needle puncture may be unnecessary in such cases.

Renal arterial infusion of acetylcholine (ACh) (40 micrograms/min) in control dogs produced an ipsilateral increase in renal plasma flow (RPF) and in sodium excretion (UNaV) without a change in glomerular filtration rate (GFR). The increase in RPF and UNaV was maintained during the infusion of ACh. In indomethacin (Indo)-treated dogs (5 mg/kg) ACh produced a transient rise in RPF and UNaV, followed by a progressive decline in RPF and UNaV. The profound renal vasoconstriction was accompanied by a decline in GFR. To determine the role of the muscarinic receptor in the renal vasodilation and in vasoconstriction produced by ACh in Indo-treated dogs, atropine at 6, 60, and 600 micrograms/min was infused into the renal artery before and during the infusion of ACh. In Indo-treated dogs, all dosages of atropine prevented renal vasoconstriction by ACh. Renal arterial infusion of atropine at 600 micrograms/min completely inhibited the renal vasodilation produced by ACh. Atropine infused at 60 micrograms/min partially inhibited, whereas 6 micrograms/min atropine failed to inhibit, the renal vasodilation produced by ACh. Our data suggest that the renal vasodilator and vasoconstrictor effects of ACh in Indo-treated dogs are mediated by two separate types of muscarinic receptors.

Acute cholinergic muscarinic blockade with pirenzepine significantly reduces meal stimulated plasma insulin and plasma glucose concentrations in clinically hyperandrogenic women with polycystic ovary syndrome. The ability of pirenzepine to reduce plasma insulin without worsening glycaemia is a particular advantage and may be therapeutically relevant. Further studies are under way to assess the usefulness of pirenzepine in long-term suppression of plasma insulin in this group of patients.