scholarly journals Ganglionic and non-ganglionic neurons in frog heart: do they differ?

2017 ◽  
Vol 26 (2) ◽  
pp. 9
Author(s):  
Darius Batulevičius ◽  
Gertrūda Skripkienė ◽  
Greta Graužinytė ◽  
Augustina Grigaitė ◽  
Valdas Skripka
Keyword(s):  
Rana Temporaria ◽  
Lucifer Yellow ◽  
Frog Heart ◽  
Total Length ◽  
Fluorescent Markers ◽  
Lucifer Yellow Ch ◽  
Frog Rana Temporaria ◽  
The Mean ◽  
Morphological Differences ◽  
Intracardiac Neurons

This study was designed to compare the morphology of neurons in relation to their distance from the major nerve trunks in the heart of the frog Rana temporaria. Seventy-nine intracardiac neurons were labelled intracellularly with fluorescent markers Lucifer Yellow CH and Alexa Fluor 568. The neurons located on the extensions of the vagus nerve were considered as ganglionic, while neurons spread loosely at further distance from these extensions were considered as non-ganglionic. The mean area of the soma in ganglionic neurons was about 25% larger than in non-ganglionic neurons. Ganglionic neurons had a higher soma area/nucleus area ratio than non-ganglionic neurons. Although both the total number and the total length of dendrite-like processes was similar between the two groups, ganglionic neurons had significantly fewer dendrite-like processes from the soma (1.5±0.3 vs. 3.9±1.0; P<0.05) and shorter total length of these processes from the soma (63±18 μm vs. 178±51 μm; P<0.05). In conclusion, ganglionic and non-ganglionic frog intracardiac neurons exhibit substantial morphological differences. We hypothesize that these differences may indicate different projections or variations in the number of their preganglionic inputs.

THE RELATION BETWEEN SEASONAL HYPERGLYCAEMIA AND THYROID ACTIVITY IN THE FROG (RANA TEMPORARIA)

1954 ◽  
Vol 10 (2) ◽  
pp. 184-191 ◽  
Author(s):  
C. L. SMITH
Keyword(s):  
Blood Sugar ◽  
Blood Sugar Level ◽  
Rana Temporaria ◽  
Previous Treatment ◽  
Thyroid Activity ◽  
In Captivity ◽  
Frog Rana Temporaria ◽  
The Mean ◽  
Fat Bodies

SUMMARY The mean blood-sugar level of frogs killed in the field without previous excitement showed no significant variation between April and October inclusive (38±1·42 mg/100 ml.). The resting blood-sugar level at other times of the year, after 2–3 days in captivity, was slightly lower. A marked hyperglycaemic response to excitement could be elicited in the majority of frogs at the spawning season (March) and throughout the summer, while it was only found in April and early May in a few frogs which showed early development of the gonadial fat-bodies. The response was much reduced in September and absent in October. The seasonal occurrence of the hyperglycaemic response paralleled the known cycle of thyroid activity, and a significant correlation was found between the blood-sugar level and thyroid condition in individual excited frogs. A significant response to excitement has been induced in spring, summer and autumn by previous treatment with thyroxine. It is suggested that the thyroid hormone inhibits the destruction of circulating adrenergic compounds. The role of temperature in limiting the hyperglycaemic response is discussed.

scholarly journals Quantitative study of synaptic boutons on frog intracardiac neurons

2017 ◽  
Vol 26 (2) ◽  
pp. 17
Author(s):  
Darius Batulevičius ◽  
Gertrūda Skripkienė ◽  
Denas Andrijauskis ◽  
Berta Kėrytė ◽  
Valdas Skripka
Keyword(s):  
Confocal Microscopy ◽  
Synaptic Vesicles ◽  
Rana Temporaria ◽  
Experimental Studies ◽  
Structure And Function ◽  
Neuronal Soma ◽  
Frog Rana Temporaria ◽  
Synaptic Boutons ◽  
And Function ◽  
Intracardiac Neurons

The frog is a useful model to study the structure and function of intracardiac neurons. The goal of this study was to evaluate the size and distribution of synaptic boutons on the intracardiac neurons in the frog Rana temporaria. Interatrial septa from four animals were double-labelled immunohistochemically for the cholinergic marker choline acetyltransferase (ChAT) and the marker of synaptic vesicles synaptophysin (SYP). One hundred intracardiac neurons were analysed by confocal microscopy. Terminals of preganglionic axons were strongly positive for ChAT, while synaptic boutons were strongly positive for both ChAT and SYP. The number of synaptic boutons per neuron ranged from 2 to 121 and was 10±2 (mean±SE). The total area of synaptic boutons ranged from 6 μm2 to 270 μm2 and was 98±6 μm2. The largest total area of synaptic boutons was found on the axonal half of neuronal soma (59±4 μm2). The total areas of synaptic boutons on both the non-axonal half of soma and the proximal axon were smaller (36±3 μm2; 6±2 μm2; P<0.001). Synaptic boutons occupied 13±1% of the area of the neuronal soma profile. Conclusions: 1) The axonal half of the soma of the frog intracardiac neuron is more densely innervated than the non-axonal half of the soma. 2) The axosomatic and axoaxonic synapses are present on frog intracardiac neurons. The study provides a framework for further experimental studies on the formation and rearrangement of synapses on frog intracardiac neurons.

Ontogeny of cholinergic and adrenergic mechanisms in the frog (Rana temporaria) heart

1992 ◽  
Vol 262 (1) ◽  
pp. R150-R161 ◽  
Author(s):  
L. L. Protas ◽  
G. R. Leontieva
Keyword(s):  
Rana Temporaria ◽  
Indirect Evidence ◽  
Neuronal Uptake ◽  
Frog Heart ◽  
Maximal Response ◽  
Heart Cells ◽  
Field Stimulation ◽  
Uptake Mechanism ◽  
Frog Rana Temporaria ◽  
Hydrolysis Of

Histochemical techniques, field stimulation, and application of autonomic drugs were used to study neurotransmission in the heart during ontogenesis of Rana temporaria. Cholinesterase (ChE)-containing fibers, fluorescent chromaffinlike cells, and fluorescent fibers were found first in the heart at tadpole stages 40, 40, and 50, respectively. Inhibitory cholinergic and stimulatory adrenergic responses to field stimulation first appeared at stages 39-40 and 42, respectively. Inhibitory responses to acetylcholine (ACh) and stimulatory responses to epinephrine (Epi) were observed as early as stages 31 and 32. The concentrations producing half-maximal response values for both neurotransmitters increased during development. Indirect evidence was obtained that the subsensitivity of tadpole hearts to ACh was due to increased hydrolysis of ACh by tissue ChE and that the subsensitivity of adult frog heart to Epi could be connected with a maturation of the neuronal uptake mechanism. The pA2 values for atropine and propranolol were 10 times greater in tadpoles than in adults. The main conclusion is that the cholino- and adrenoreactive systems appear in the frog heart cells before they become innervated and the sensitivity of these systems to neurotransmitters does not increase with innervation.

The First Record of Tesselated Snake, Natrix tesselata Laurenti, 1768 in the Central Chernozem Territory of Russia and Some Other Results of the Herpetological Research in the Upper Don

2011 ◽  
Vol 4 (2) ◽  
pp. 192-194
Author(s):  
Georgy A. Lada ◽  
V. Y. Nedosekin
Keyword(s):  
Rana Temporaria ◽  
First Record ◽  
Isolated Population ◽  
Common Frog ◽  
Northern Border ◽  
Frog Rana Temporaria ◽  
Bombina Bombina ◽  
Central Chernozem

A small isolated population of tesselated snake, Natrix tesselata was found in the Upper Don (Lipetsk Region, Russia). It is the first record of this species in the Central Chernozem Territory of Russia, which is separated from the northern border of the main range by the distance of about 200 km. An isolated population of common frog, Rana temporaria and phenetically peculiar population of fire-bellied toad, Bombina bombina are found here too. Faunistic aspect of new herpetological records is discussed.

Small woods positively influence the occurrence and abundance of the common frog (Rana temporaria) in a traditional farming landscape

2015 ◽  
Vol 36 (4) ◽  
pp. 417-424 ◽  
Author(s):  
Alexandre Boissinot ◽  
Pierre Grillet ◽  
Aurélien Besnard ◽  
Olivier Lourdais
Keyword(s):  
Western Europe ◽  
Rana Temporaria ◽  
Common Frog ◽  
Traditional Farming ◽  
Critical Determinant ◽  
Southern Margin ◽  
Frog Species ◽  
Frog Rana Temporaria ◽  
The Common ◽  
Extensive Farming

Traditional farming landscape in western Europe is made of a complex mosaic of pastures, cultures, ponds and hedgerows connected with woods. Previous observations in the common frog species suggest that lowland populations are closely associated to wood cover and our aim was to test the validity of this assumption. We studied common frog occurrence and abundance in western central France (Deux-Sèvres department) close to the southern margin of lowland distribution. Our results pointed out that the proportion of woods surface around sampled areas (1 ha) was a critical determinant of common frog presence and abundance. Extensive farming, which maintains a mosaic of small woods, may provide a robust conservation tool for this species.

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