Spasmogenic

Asthma is characterized by variable symptoms such as wheeze, shortness of breath and coughing and is usually associated with airway inflammation, with variably reduced spirometric indices [4, 5], with increased non-specific airway responsiveness (AR) to spasmogens [6, 7] and increased levels of semm immunoglobulin E (IgE) and eosinophils [8-10]. The symptoms of asthma are primarily due to excessive airway narrowing, which leads to an increased resistance to airflow, especially during forced expiration, and produces characteristic spirometric findings. A cardinal feature of asthma is that airway narrowing is reversible either spontaneously or as the result of therapy. 

Ergot alkaloids (ergotamine, ergonovine) also exhibit certain nonselective a-adrenoblocking activity however, they primarily exhibit spasmogenic action on smooth muscle, causing a constriction of blood vessels. 

Spasmogenic activity. Ethanol (95%) extract of the fresh leaf and stem, administered to guinea pigs at a dose of 0.5 mL/L, was active on ileum. Water extract of the fresh leaf and stem, administered intraperi-toneally to guinea pigs at a dose of 0.5 mL/L, was active on ileum . 

Serum HDL-lowering effect. Seed fixed oil, administered to male hamsters at a concentration of 19% of diet, was inactive Serum LDL-lowering effect Seed oil, administered orally to male adults at a dose of 30.5% of diet, produced weak activity ". Spasmogenic activity. Water extract of the dried leaf, administered to rats at a dose of 0.1 pg/mL was active on ileum and a dose of 0.3 pg/mL was active on ileum vs acetylcholine-induced contractions ... 

Radical scavenging effect. Seed oil, in cell culture, was active on astrocytes vs peroxide radical scavenging, IC50 27461 ppm . Spasmogenic activity. Methanol (70%) extract of the seed, administered to guinea pigs at a dose of 1 mg/mL, was active on the uterus and ileum. The effect was abolished... 

Sp. Abbreviation for species (singular). Spp. Abbreviation for species (plural). Spasmogenic. Relating to the production of, or causing spasms. 

The spasmogenic activity of 93a and 93b was identified as an indirect cholinergic action. Additionally both esters exhibit a weak anticholinergic and a weak noncompetitive papaverine-like action. Great differences between 93a and 93b were not observed. 

Against the spasmogens BaCl2 and histamine, all compounds exhibit relative weak spasmolytic actions. Only in the case of pair 98a/98b a little, but significant difference in the histaminolytic properties was observed the silicon compound 98b acts stronger than the carbon analogue 98a. 

In vitro tests (isolated guinea pig ileum) of the pair 157a/15 7b and some of their derivatives (159-167) were carried out with the spasmogens carbachol, histamine and BaCl2 (Table 14)118 Most of the compounds exhibit a spasmolytic acti-... 

In rats, papaverine had a choleretic effect (271). It caused relaxation of the duodenum, of the sphincter of Oddi, and of the muscles of the bile duct (272-277). It paralyzed the spasmogenic effect of morphine on these structures. Papaverine (0.36 g) in combination with 100 ml of 60% sorbitol, administered to man by means of a duodenal probe, showed a higher choleretic and a lower cholecystokinetic effect than a 30% solution of magnesium sulfate (277). 

A further practical consideration of using low ion concentration to induce tone is that the contractions can be small and not well maintained. A possible solution to this problem is to enhance the tone by using the calcium agonist. Bay K 8644 (45), but this further complicates the assay [57], A simpler alternative is to use a spasmogen-induced contraction that can be potently relaxed by cromakalim (1) (for example, noradrenaline-induced contraction in vascular tissue), and then compare the compound under examination against high K ion concentration [58]. 

However, it is difficult to extrapolate PC20 changes after treatment with beta2-agonists to the clinical outcome. There is an assumption that if PC20 falls, the patient is more likely to suffer acute attacks when exposed to spasmogens, allergens, and exercise. However, the loss of bronchoprotective effect has not so far been shown to increase morbidity or mortality in asthmatic patients. 

Regular exposure to a racemate, especially during or after an allergic reaction, will cause hyper-reactivity to spasmogens, and this could be due to an effect of the 5-isomer. This effect is not seen immediately, because of beta2-adrenoceptor-mediated bronchodilatation by the R-isomer. 

In contrast to many other smooth muscle types, ASM is regarded as being multi-unit rather than single unit, which means that each smooth muscle cell is individually innervated. This is associated with a relative lack of gap junctions which normally provide a low resistance electrical pathway for cell to cell communication. Spontaneous electrical activity is rarely observed in ASM cells and action potentials only occur in exceptional circumstances, the usual electrical response to spasmogens being graded depolarization without the overall muscle bundle acting as a syncytium. 

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