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In an uncontrolled trial, patients with IgA nephropathy (IgAN) were treated with drugs that can alter the intestinal mucosal permeability to food antigens. These drugs are known to ameliorate urinary abnormalities and histological lesions of IgAN associated with ulcerative colitis or Crohn's disease [5-aminosalicylic acid (5-ASA)] or to prevent, in mice, the induction of IgAN-like disease by oral immunization [disodium cromoglycate (SCG)]. Nine patients [serum creatinine (s-Cr) less than 2 mg/dl; 24-hour proteinuria higher than 1.5 g, but not nephrotic) were treated with 5-ASA (2.4 g/day for 6 months); 9 similar patients were treated with SCG (400 mg/day for 6 months); the follow-up extended to 6 months after stopping therapy. The 5-ASA group showed a slight but not significant decrease in s-Cr, 24-hour/proteinuria, IgA circulating immune complexes (IgA-CIC) and IgA rheumatoid factor (IgA-RF); serum beta 2-microglobulin and serum IgA were unchanged; 2 of 9 treated patients showed, after 6 months of therapy, a reduction in proteinuria of more than 50% that lasted for the subsequent 18 months. The SCG-treated group showed a slight but not significant increase in 24-hour proteinuria and a significant decrease in serum IgA; unchanged were s-Cr, IgA-CIC, IgA-RF, serum beta 2-microglobulin; no patient treated with SCG showed a reduction in proteinuria of more than 50%. At the dosages and for the periods used, 5-ASA and SCG did not show a significant influence on clinical and laboratory parameters of disease in IgAN; other trials with increased dosages are warranted to definitely ascertain the possible therapeutic role of these drugs in IgAN.

The function of the tuberoinfundibular dopaminergic (TIDA) neurons of 49 rats bearing oestradiolvalerate (EV)-induced prolactin (Prl) secreting tumours (prolactinomas) was evaluated in vivo, 7 months after discontinuation of EV-treatment, with neuroactive drugs acting via stimulation or inhibition of DA neurotransmission. Based on the size and morphologic appearance of the pituitary and on determination of plasma Prl levels, rats previously treated with EV could be divided into those bearing macro- (31/49) and those bearing microprolactinomas (18/49). Administration of the indirect DA agonist drug nomifensine (10 mg/kg iv) lowered plasma Prl levels in control rats, but failed to do so in rats bearing either macro- or microprolactinomas. Administration of the DA receptor antagonist domperidone (50 μg/kg ip) or the synthetic enkephalin analogue FK 33-824 (1 mg/kg ip) failed to induce a rise in plasma Prl in rats with macro-, but induced a clear-cut rise in plasma Prl in those with microprolactinomas. Prl unresponsiveness to all three neuroactive drugs indicates that long time after EV withdrawal TIDA neuronal function is still highly impaired in rats bearing EVinduced macroprolactinomas. The impairment of TIDA neuronal function would be of lesser extent in rats bearing microprolactinomas as revealed by a defective response to only one of the three applied neuroendocrine probes.

Dermorphin, a heptapeptide isolated from the skin of the frogs Phillomedusa sauvagei and Phillomedusa rhodei, is endowed with potent peripheral and central opioid-like activity. Intracerebroventricular (icv) injection of dermorphin (31.2, 62.5 and 125 pmol/100g) induced in ovariectomized (OVX) rats dose related rises and decreases in prolactin (PRL) and luteinizing hormone (LH) levels, respectively. The aim of this work was to evaluate the same endocrine responses after administration of shorter peptide amide homologues, related to the N-terminal sequence of dermorphin. These compounds retain a substantial analgesic activity although the latter decreases with the decrease in the number of amino acid residues. Icv administration of the hexapeptide homologue (dermorphin 1-6 amide) to OVX rats did not induce any PRL rise or LH inhibition, even at the high dose of 250 pmol/100g. The pentapeptide (dermorphin 1-5 amide), instead, increased PRL and decreased LH secretion, although the effect was significant only at the dose of 250 pmol/100g. Administration of the tetrapeptide (dermorphin 1-4 amide) induced a significant PRL rise and LH inhibition at both the doses of 125 and 250 pmol/100g. The tetrapeptide was the smallest fragment of the dermorphin moiety which caused endocrine responses while the tripeptide (dermorphin 1-3 amide) was completely ineffective in this context. These data indicate that a complete dissociation exists between the behavioral and endocrine effects of the dermorphin homologues examined. In fact, shorter dermorphins whose analgesic potency was directly related to the number of amino acids, exhibited an opposite pattern in evoking endocrine effects.