Neuromuscular activity in sea anemone Calliactis parasitica (Couch)
نویسندگان
چکیده
منابع مشابه
The transmission of impulses in the ectodermal slow conduction system of the sea anemone Calliactis parasitica (Couch).
1. The SS 1 fatigues in response to repetitive electrical stimulation. This fatigue is manifested by an increased conduction delay and a decreased SS 1 pulse amplitude. 2. Continued repetitive stimulation leads to the failure of the system. Recovery may take many seconds. Narrow strips of column fail more rapidly than wide strips. 3. The increased conduction delay is explained in terms of a dec...
متن کاملControl of mouth opening and pharynx protrusion during feeding in the sea anemone Calliactis parasitica.
1. Activity in all three known conducting systems (the nerve net, SS1, and SS2) may accompany feeding in Calliactis. The most marked response is an increase in pulse frequency in the SS2 (the endodermal slow conducting system) during mouth opening and pharynx protrusion. 2. Electrical stimulation of the SS2 at a frequency of one shock every 5 s elicits mouth opening and pharynx protrusion in th...
متن کاملControl of the pacemaker system of the nerve-net in the sea anemone Calliactis parasitica.
1. The rhythm of spontaneous nerve-net pulses is reset by intercalated evoked nerve-net pulses. 2. The origin of spontaneous nerve-net pulses can shift during a burst. There seem to be many potential pacemakers, widely distributed throughout the body, but apparently absent from the tentacles. 3. If a spontaneous or evoked pulse in the endodermal slow conduction system (SS 2) occurs during a bur...
متن کاملExcitatory and inhibitory control of inherent contractions in the sea anemone Calliactis parasitica.
The shape of the column of a sea anemone depends partly on the relative state of contraction of two antagonistic muscle groups in the body wall endoderm. These muscles, the circulars and the longitudinals (parietals), are attached to the mesogloea and act against the hydrostatic pressure in the coelenteron. The circulars form a continuous muscle sheet whereas the parietals lie only where mesent...
متن کاملDelayed initiation of SS1 pulses in the sea anemone Calliactis parasitica: evidence for a fourth conducting system.
1. Single electrical shocks to the column sometimes elicit a series of 1-6 pulses in the SS1 (ectodermal slow system) but the first pulse does not appear until 5-28 s after stimulation. These pulses occur in addition to the early SS1 pulse which follows every shock and which has a conduction delay of less than 1 s. 2. The threshold of the delayed SS1 response is different from the thresholds of...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of the Marine Biological Association of the United Kingdom
سال: 1958
ISSN: 0025-3154,1469-7769
DOI: 10.1017/s0025315400005786