Reproduction in Aplysia californica: correlations between egg laying in vivo and egg release in vitro

1980 ◽  
Vol 58 (11) ◽  
pp. 2163-2166 ◽  
Author(s):  
F. Edward Dudek ◽  
Amd Bonnie Soutar ◽  
Stephen S. Tobe
Keyword(s):  
Aplysia Californica ◽  
Egg Laying ◽  
Previous Episode ◽  
Laboratory Conditions ◽  
Release In Vitro

Aspects of egg laying by isolated Aplysia californica and egg release from ovotestis fragments were compared under laboratory conditions. The volume of eggs laid per episode increased as a function of time since the previous episode of egg laying. Egg output in vivo and egg release in vitro were maximal in autumn and minimal in spring, but a factor in the parietovisceral ganglion evoked egg release from ovotestis fragments throughout the year. These data are consistent with previous studies which have suggested that the effects of season and egg-laying history on egg laying involve substantial changes in the ovotestis.

NEURONAL FEEDBACK IN EGG-LAYING BEHAVIOUR OF THE POND SNAIL LYMNAEA STAGNALIS

1993 ◽  
Vol 178 (1) ◽  
pp. 251-259 ◽  
Author(s):  
G. P. Ferguson ◽  
A. W. Pieneman ◽  
R. F. Jansen ◽  
A. Ter Maat
Keyword(s):  
Lymnaea Stagnalis ◽  
Aplysia Californica ◽  
Experimental System ◽  
Egg Laying ◽  
Neuroendocrine Cells ◽  
Behaviour Pattern ◽  
Pond Snail ◽  
Egg Laying Behaviour

The egg-laying behaviour of gastropod molluscs is controlled by peptidergic neuroendocrine cells and has provided an important experimental system for behavioural neurobiology. The genes that code for multiple peptides have been sequenced and the peptides themselves have been identified, thus enabling us to investigate how they act on the nervous system to produce the overt behavioural pattern (reviewed by Geraerts et al. 1988). The two animals that have been studied most extensively are the opisthobranch Aplysia californica and the pulmonate Lymnaea stagnalis. In both cases, the peptidergic neurones controlling egg laying are normally electrically silent (both in vivo and in vitro; Kupfermann, 1967; Pinsker and Dudek, 1977; Kits, 1980; Ter Maat et al. 1986) and produce multiple peptides (Rothman et al. 1983; Geraerts et al. 1985; Sigvardt et al. 1986), which are cleaved from a common protein precursor (Scheller et al. 1983; Vreugdenhil et al. 1988). Before egg laying, the cells produce a long-lasting discharge of action potentials (Pinsker and Dudek, 1977; Ter Maat et al. 1986). This electrical discharge initiates egg-laying behaviour, and during it the peptides (one of which initiates ovulation) are released into the blood. The demonstration, in Aplysia californica, that these peptides could have various effects on the activity of central neurones (reviewed by Mayeri and Rothman, 1985) led to the hypothesis that egg-laying behaviour is a neuroendocrine fixed action pattern controlled and coordinated by the concerted actions of the released peptides (Scheller and Axel, 1984). This hypothesis is also thought to apply to Lymnaea stagnalis (Vreugdenhil et al. 1988) because of the structural similarities between precursors of Aplysia californica and Lymnaea stagnalis egg-laying hormones. In this paper we investigate how the sequence of the various components of the egg-laying behaviour pattern is achieved.

Pharmacology of 5-HT1A Receptors: Critical Aspects

CNS Spectrums ◽  
1998 ◽  
Vol 3 (10) ◽  
pp. 17-38 ◽  
Author(s):  
Franco Borsini
Keyword(s):  
Receptor Subtypes ◽  
Laboratory Conditions ◽  
In Vivo Effects ◽  
Critical Aspects

AbstractMyriad difficulties exist in analyzing the pharmacology of the serotonin 1A (5-HT1A) receptor. The receptor may demonstrate a different activity depending on the tissue or species used for analysis, the agent used, laboratory conditions, and differences between in vitro and in vivo effects of compounds. Affinity for 5-HT receptors also varies widely, presenting difficulties in drawing definitive conclusions on affinity values for various compounds. At least two possibilities exist to explain the diversity of pharmacology of 5-HT receptors. First, it is possible that different 5-HT1A receptor subtypes exist. Second, the 5-HT1A receptors may play a far more complex role than previously believed.

Kinematic models of the buccal mass of Aplysia californica.

1998 ◽  
Vol 201 (10) ◽  
pp. 1563-1583 ◽  
Author(s):  
R F Drushel ◽  
D M Neustadter ◽  
I Hurwitz ◽  
P E Crago ◽  
H J Chiel
Keyword(s):  
Neural Control ◽  
Kinematic Model ◽  
Aplysia Californica ◽  
Relative Location ◽  
Marine Mollusc ◽  
Buccal Mass ◽  
Kinematic Models ◽  
Made In

The feeding behavior of the marine mollusc Aplysia californica is an intensively studied model system for understanding the neural control of behavior. Feeding movements are generated by contractions of the muscles of the buccal mass. These muscles are internal and cannot be visualized during behavior. In order to infer the movements of the muscles of the buccal mass, two kinematic models were constructed. The first kinematic model assumed that the complex consisting of the pincer-like radula and the underlying odontophore was spherical in shape. In this model, the radula/odontophore was moved anteriorly or posteriorly and the more superficial buccal muscles (I1/I3 and I2) were fitted around it. Although the overall buccal mass shapes predicted by this model were similar to those observed in vivo during protraction, the shapes predicted during retraction were very different. We therefore constructed a second kinematic model in which the shape of the radula/odontophore was based on the shapes assumed by those structures in vitro when they were passively forced into protraction, rest or retraction positions. As each of these shapes was rotated, the second kinematic model generated overall shapes of the buccal mass that were similar to those observed in vivo during swallowing and tearing, and made predictions about the antero-posterior length of the buccal mass and the relative location of the lateral groove. These predictions were consistent with observations made in vivo and in vitro. The kinematic patterns of intrinsic buccal muscles I1 and I2 in vivo were estimated using the second model. Both models make testable predictions with regard to the functions and neural control of intrinsic buccal muscles I2 and I3.

Incorporation of Methotrexate in Calcium Phosphate Cement: Behavior and Release in Vitro and in Vivo

Orthopedics ◽  
2009 ◽  
Vol 32 (1) ◽  
pp. 27-6 ◽  
Author(s):  
Zhiping Yang ◽  
Dong Li ◽  
Jian Han ◽  
Jianmin Li ◽  
Xin Li ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Release In Vitro

PROTEASE INHIBITOR GABEXATE MESILATE INHIBITS TNF RELEASE IN VITRO AND IN VIVO

Shock ◽  
1995 ◽  
Vol 4 (Supplement) ◽  
pp. 22
Author(s):  
Fukushima Ryoji ◽  
Saito Hideaki ◽  
Lin Ming-Tsan ◽  
Inoue Tomomi ◽  
Fakatsu Kazuhiko ◽  
...  
Keyword(s):  
Protease Inhibitor ◽  
Gabexate Mesilate ◽  
Release In Vitro

Reversion mutation of cDNA CA8-204 minigene construct produces a truncated functional peptide that regulates calcium release in vitro and produces profound analgesia in vivo

2020 ◽  
Vol 31 (9-12) ◽  
pp. 287-294
Author(s):  
Udita Upadhyay ◽  
Gerald Z. Zhuang ◽  
Luda Diatchenko ◽  
Marc Parisien ◽  
Yuan Kang ◽  
...  
Keyword(s):  
Calcium Release ◽  
Release In Vitro ◽  
Functional Peptide

NIR-Responsive Copolymer Upconversion Nanocomposites for Triggered Drug Release in Vitro and in Vivo

2018 ◽  
Vol 2 (1) ◽  
pp. 495-503 ◽  
Author(s):  
Yeye Zhang ◽  
Guangzhao Lu ◽  
Yuan Yu ◽  
He Zhang ◽  
Jie Gao ◽  
...  
Keyword(s):  
Drug Release ◽  
Triggered Drug Release ◽  
Release In Vitro
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