Izazivanje želučanih ulceraclja perivagalnom injekcijom tetanus toksina

Gastric erosions have been produced in rabbits by subperitoneal injections of tetanus toxin along the vagus nerves in relation to the oesophagus or anterior wall of the stomach, and into the central end of the cut cervical vagus on one side. Ten rabbits injected in this way with 0.3-1 mg of toxin all showed acute erosions, often haemorrhagic, after periods of 12-146 hr. (a) Four control rabbits treated identically with boiled toxin did not exhibit ulceration. (b) Of 19 normal rabbit stomachs, examined at random, only one had a small erosion. (c) The intravenous injection of toxin was without ulcerative effect. In 9 rabbits the vagi were both cut subdiaphragmatically. Four were killed either 6 or 42 days later, and had no erosion. The other 5 were killed (or died) at comparable times but had been injected in the usual way with toxin 28-48 hr. before death; all showed erosions.Želučani ulkusi bili su izazvani kod kunića subperitonealnim injekcijama tetanus toksina uzduž vagusa na ezofagusu i prednjoj stijenci želuca, i injiciranjem centralnog kraja prerezanog cervikalnog vagusa s jedne strane. 10 kunića bilo je injicirano na taj način dozama od 0,3-1 mg toksina i svi su pokazali akutne erozije, često hemoragične, nakon perioda od 12-146 sati. 4 kontrolna kunića, koji su bili tretirani na isti način kuhanim toksinom, nisu pokazali znakove ulceracija, Izvršeni su pregledi želudaca 19 normalnih kunića, te je samo kod jednoga nađena mala erozija. Intravenozna injekcija toksina nije izazvala ulceracioni efekt. Kod 9 kunića bila su oba vagusa prerezana subdijafragmalno, 4 su bila ubijena nakon 6-42 dana i nisu pokazivali nikakvih erozija. Ostalih 5 je ubijeno (ili je uginulo)) u istim vremenskim razmacima. Njima se na uobičajeni način injicirao toksin 28-48 sati prije smrti, i svi su pokazivali erozije

Inhibition of post-ganglionic motor transmission in vas deferens by indirectily acting sympathomimetic drugs

Usando um campo elétrico estimulador, com séries curtas de pulsos (menor que 10 por série), a transmissão motora pós-ganglionar nos vasos deferentes de mamíferos foi posteriormente analisada do ponto de vista farmacológico

Robert F. Furchgott, Nobel laureate (1916-2009) - a personal reflection

Robert F. Furchgott, pharmacologist and joint winner of the Nobel Prize for Medicine or Physiology (1998) died on the 12th of May 2009 aged 92. By unlocking the astonishingly diverse biological actions of nitric oxide, Furchgott leaves behind a rich legacy that has both revolutionized our understanding of human physiology and stimulated new and exciting opportunities for drug development in a wide range of pathological conditions. In this article, William Martin, who worked with Furchgott for 2 years (1983-1985), following the exciting discovery of endothelium-derived relaxing factor/nitric oxide, pays tribute to his close friend and colleague

The Rise and Fall, and the Rise (Again) of Feminist Research in Music: 'What Goes Around Comes Around'

This article reports from a two-phase study that involved an analysis of the extant literature followed by a three-part survey answered by seventy-one women composers. Through these theoretical and empirical data, the authors explore the relationship between gender and music’s symbolic and cultural capital. Bourdieu’s theory of the habitus is employed to understand the gendered experiences of the female composers who participated in the survey. The article suggests that these female composers have different investments in gender but that, overall, they reinforce the male habitus given that the female habitus occupies a subordinate position in relation to that of the male. The findings of the study also suggest a connection between contemporary feminism and the attitudes towards gender held by the participants. The article concludes that female composers classify themselves, and others, according to gendered norms and that these perpetuate the social order in music in which the male norm dominates

Spontaneous purinergic neurotransmission in the mouse urinary bladder

Spontaneous purinergic neurotransmission was characterized in the mouse urinary bladder, a model for the pathological or ageing human bladder. Intracellular electrophysiological recording from smooth muscle cells of the detrusor muscle revealed spontaneous depolarizations, distinguishable from spontaneous action potentials (sAPs) by their amplitude (< 40 mV) and insensitivity to the L-type Ca(2+) channel blocker nifedipine (1 μm) (100 ± 29%). Spontaneous depolarizations were abolished by the P2X(1) receptor antagonist NF449 (10 μm) (frequency 8.5 ± 8.5% of controls), insensitive to the muscarinic acetylcholine receptor antagonist atropine (1 μm) (103.4 ± 3.0%), and became more frequent in latrotoxin (LTX; 1 nm) (438 ± 95%), suggesting that they are spontaneous excitatory junction potentials (sEJPs). Such sEJPs were correlated, in amplitude and timing, with focal Ca(2+) transients in smooth muscle cells (measured using confocal microscopy), suggesting a common origin: ATP binding to P2X(1) receptors. sAPs were abolished by NF449, insensitive to atropine (126 ± 39%) and increased in frequency by LTX (930 ± 450%) suggesting a neurogenic, purinergic origin, in common with sEJPs. By comparing the kinetics of sAPs and sEJPs, we demonstrated that sAPs occur when sufficient cation influx through P2X(1) receptors triggers L-type Ca(2+) channels; the first peak of the differentiated rising phase of depolarizations – attributed to the influx of cations through the P2X(1) receptor – is of larger amplitude for sAPs (2248 mV s(−1)) than sEJPs (439 mV s(−1)). Surprisingly, sAPs in the mouse urinary bladder, unlike those from other species, are triggered by stochastic ATP release from parasympathetic nerve terminals rather than being myogenic