Summary:The vasomotor responses of tachykinins have been studied in the cerebral vasculature of human, pig, cat, and guinea pig, Substance P (SP), neurokinin A (NKA), neurokinin B (NKB), and neuropeptide K (NPK) induced concentration-dependent relaxations of pre con tracted cerebral arteries in all species when examined by a sensitive in vitro technique, In addition, the relaxant responses to SP, NKA, and NKB were studied in cat pial arterioles by peptide microapplication in situ. In human pial vessels, the order of relaxant potency was SP > N KB > NKA > NPK; in the pig middle cerebral artery, there was no difference in potency between the tachykinins; in the cat middle cerebral artery, SP = NKB > NKA = NPK; and in the guinea pig basilar artery, SP :» NPK = NKA > NKB. Responses induced by SP, NKA, and NKB in the cat were comparable in vitro and in situ. Removal of the endothelium abolished relaxation induced by all four tachykinins. The relaxant responses of guinea It is well recognized that substance P (SP), which is a peptide involved in the mechanisms of nocicep tion, also produces strong relaxation of cerebral ar teries in vitro and in situ (Edvinsson et al. , , 1982. SP is present in afferent nerve fibers (Edvins son et al. , 1981(Edvins son et al. , , 1982(Edvins son et al. , , 1983 originating in trigem inal nerve cell bodies that supply cerebral blood vessels (Liu-Chen et al. , 1983a,b). The trigemino cerebrovascular system has been thought to initiate Received October 22, 1990; revised December 13, 1990; ac cepted February 1, 1991. Address correspondence and reprint requests to I. Jansen at Department of Experimental Research, University of Lund, Malmo General Hospital, S-214 01 Malmo, Sweden.Ab b revi ati ons used : CGRP, calcitonin gene-related peptide; 5-HT, 5-hydroxytryptamine; NKA; neurokinin A; NPK, neuro peptide K; NKB, neurokinin B; PPT, preprotachykinin; PGF2a, prostaglandin F2a; SP, substance P. 567pig basilar arteries to SP, NKA, and NPK were compet itively antagonized by the SP antagonist Spantide. How ever, Spantide lowered the I max of the NKB concentra tion-response curve without any rightward shift, suggest ing action at a different site than the other tachykinins. In the guinea pig basilar artery, the relaxation seems to be exerted via a N K -1 receptor subtype while the receptor subtype is more unclear in cerebral arteries from human, cat, and pig. It is concluded that relaxations induced by SP, NKA, NKB, and NPK are dependent on the endo thelium, and are antagonized either competitively or non competitively by the SP antagonist Spantide. The origin of tachykinins acting through the endothelium is dis cussed. Key Words: Cerebral arteries-In vitro pharma cology-In situ-Substance P-Neurokinin A Neuropeptide K-Neurokinin B-Cat-Guinea pig Pig-Human. (Nawa et al. , 1983(Nawa et al. , , 1984Krause et al. , 1985). a-PPT A contains SP while f3-PPT A and T-PPT A contain both SP and NKA.NPK is a prolonged form of NKA and is derived from f3-PPT A. NKB is derived from PPT B, which is g...

In prolactin-secreting giant adenomas, cabergoline treatment is the first line approach. Surgery and/or radiotherapy are indicated when the tumour is resistant to medical treatment and continues growing, causing visual field impairment. Data concerning other therapeutic approach are scanty. Although PRL-secreting tumours may express somatostatin receptors type 2, 3 and 5, somatostatin analogs treatment is generally ineffective and peptide receptor radionuclide therapy (PRRT) has never been reported. A 58 year-old woman complaining of severe neurological symptoms caused by a giant prolactinoma, relapsing after surgery and not-responding to dopamine-agonists and octreotide LAR treatment, underwent four cycles of PRRT with 111-Indium-DTPA-octreotide with remarkable tumour shrinkage and a significant improvement in clinical conditions. No side effects were reported. This is the first report on the effectiveness and safety of PRRT with radio-labelled somatostatin analogs in a patient with aggressive giant prolactinoma resistant to conventional treatment.

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Olfactory groove meningiomas, arising in an area of maximal brain compliance to slowly progressive neoplastic growth, may attain surprisingly large size with relatively minimal symptoms.1,2 The bifrontal craniotomy is currently indicated as the preferred approach for large-sized olfactory meningiomas,2-11 including refinements such as the supraorbital approach on the nondominant side of the flap.'2 The pterional-transsylvian route represents also an alternate exposure for microsurgical excision of frontobasal tumors.13-15 Although this approach has been described already for olfactory groove meningiomas, 16-17 tumors of very large size were not directly addressed in the publications. This paper describes the application of this approach in six patients harboring giant olfactory meningiomas exceeding 6 cm in diameter. Aims of this article are: (1) to specifically address the issue of suitability of the pterionaltranssylvian route for giant-sized olfactory meningiomas; and (2)