Sounding Response of the Kokanee and Sockeye Salmon

1968 ◽  
Vol 25 (6) ◽  
pp. 1115-1131 ◽  
Author(s):  
H. H. Harvey ◽  
W. S. Hoar ◽  
C. R. Bothern
Keyword(s):  
Sockeye Salmon ◽  
Bladder Wall ◽  
Muscle Fibers ◽  
Circular Muscle ◽  
Adrenergic Blockade ◽  
Kokanee Salmon ◽  
Associated Gas ◽  
Treated Fish ◽  
Gas Loss ◽  
Adrenergic Blocking

When frightened, sockeye and kokanee salmon dive into deeper waters. This is termed the "sounding response."The sounding response in these fish is accompanied by the expulsion of gas from the swimbladder via the pneumatic duct. This gas loss is active and results from the contraction of the circular muscle fibers in the wall of the swimbladder.Gas loss on sounding is reduced or obviated after exposure to adrenergic blocking agents and enhanced in fish treated with sympathomimetics. Circular muscle fibers in intact and isolated strips of swimbladder contracted in response to sympathomimetics, but this response was prevented after adrenergic blockade. These results suggest the concentration of the swimbladder and associated gas expulsion is under adrenergic control.In untreated fish, an average pressure of 28.1 mm Hg was required to force gas out of the swimbladder through the pneumatic duct. In antropine-treated fish this duct-release pressure fell to an average of 0.2 mm Hg. This suggests constriction of the pneumatic duct is under cholinergic control.Histologically, the pneumatic duct was continuous with the oesophagus and extended as a convoluted duct to the anterior end of the swimbladder. Smooth muscle fibers surrounded the duct along its length and some striated fibers were present at the point where the duct joined the oesophagus. Occlusion of the pneumatic duct may be through the contraction of either of these types of fibers.The term "Gasspuckreflex" as originally used by Franz described the loss of gas from the swimbladder of physostomes in response to decompression. The authors suggest this term be reserved for this passive loss of gas, and not applied to fright-induced gas loss, resulting from active contraction of the bladder wall.

Proliferative kidney disease and Sphaerospora oncorhynchi in wild-caught salmonids from the Puntledge River system, Vancouver Island, British Columbia

1995 ◽  
Vol 52 (S1) ◽  
pp. 13-17 ◽  
Author(s):  
M.L. Kent ◽  
M. Higgins ◽  
D.J. Whitaker ◽  
H. Yokoyama
Keyword(s):  
British Columbia ◽  
Kidney Disease ◽  
Chinook Salmon ◽  
Sockeye Salmon ◽  
Natural Infection ◽  
Vancouver Island ◽  
Renal Tubules ◽  
Kokanee Salmon ◽  
Proliferative Kidney Disease ◽  
Sexually Mature

Proliferative kidney disease (PKD), caused by the PKX myxosporean, was observed in kokanee salmon (non-anadromous sockeye salmon) (Oncorhynchus nerka) and chinook salmon (O. tshawytscha) collected from the Puntledge River, Vancouver Island, British Columbia in July 1993. This is the first report of a natural infection of PKX in either captive or wild sockeye salmon. All 14 underyearling kokanee salmon and the one underyearling chinook salmon exhibited numerous PKX organisms and associated chronic inflammation in the renal interstitium. Thirty-eight percent of sexually mature kokanee salmon collected in the autumn of 1993 from Comox Lake (which drains into the Puntledge River) were infected with Sphaerospora oncorhynchi, Kent, Whitaker and Margolis, 1993 in the renal tubules, while immature cutthroat trout (O. clarki) and coho salmon (O. kisutch) from the same collection did not exhibit myxosporean spores in the kidney. The kidneys of threespine stickleback (Gasterosteus aculeatus) and prickly sculpin (Cottus asper) collected from the Puntledge River during the summer were all infected with a Myxobilatus sp., but no organisms suggestive of PKX or Sphaerospora were observed. This study further supports the hypothesis that PKX is a developmental stage of S. oncorhynchi, which may sporulate only in sexually mature salmonids.

"Residual" and kokanee salmon in Cultus lake

1938 ◽  
Vol 4a (3) ◽  
pp. 192-218 ◽  
Author(s):  
W. E. Ricker
Keyword(s):  
Sockeye Salmon ◽  
Anadromous Fish ◽  
Kokanee Salmon ◽  
Rate Of Growth

The sockeye salmon in Cultus lake are of three kinds: (1) the normal anadromous stock, (2) a "residual" group, not anadromous, but largely or perhaps wholly the progeny of anadromous fish, and (3) a stock of non-anadromous kokanee, which have no known connection with the anadromous or residual fish at the present time. Morphological and physiological peculiarities distinguish the three kinds of sockeye at maturity. In the segregation of the progeny of a spawning of anadromous fish into migrant and residual groups, rate of growth and sex play a determining role.

Effect of beta-adrenergic blockade and inhibitors of angiotensin II and prostaglandins on renal autoregulation

1975 ◽  
Vol 229 (3) ◽  
pp. 731-736 ◽  
Author(s):  
RJ Anderson ◽  
MS Taher ◽  
RE Cronin ◽  
KM McDonald ◽  
RW Schrier
Keyword(s):  
Angiotensin Ii ◽  
Renin Angiotensin System ◽  
Blocking Agent ◽  
Adrenergic Blockade ◽  
Beta Adrenergic ◽  
Renal Autoregulation ◽  
Beta Receptor ◽  
Adrenergic Blocking

The role of the renin-angiotensin system and prostaglandins in renal autoregulation was investigated in dog kidneys in situ. Renal autoregulation during decreases in renal arterial pressure (RAP) was examined in animals pretreated with a competitive antagonist of angiotensin ii, [1-sarcosine, 8-glycine] angiotensin II, or one of two chemically dissimilar inhibitors of prostaglandin synthetase, indomethacin and meclofenamate. Because of recent evidence suggesting a role for an intrarenal beta receptor in regulating renin release, renal autoregulation was also examined in animals treated with the beta-adrenergic blocking agent propranolol. In all groups of animals constancy of glomerular filtration rate (GFR) and renal blood flow (RBF) was observed after substantial decreases in RAP to a range of 70-90 mmHg. These studies therefore do not provide evidence in support of a role for angiotensin II, prostaglandins, or an intrarenal beta receptor as mediators of the renal autoregulation of GFR or total RBF.

Nutrients in Salmonid Ecosystems: Sustaining Production and Biodiversity

2003 ◽  
Keyword(s):  
Primary Production ◽  
Sockeye Salmon ◽  
Secchi Depth ◽  
Zooplankton Biomass ◽  
Snake River ◽  
Forage Production ◽  
Meteorological Forcing ◽  
Kokanee Salmon ◽  
Compensation Depth ◽  
Large Populations

<em>Abstract.</em>—Snake River sockeye salmon <em>Oncorhynchus nerka </em>once inhabited five prealpine lakes in the Sawtooth Valley, Idaho, but are presently reduced to the Redfish Lake stock. Declining returns to Redfish Lake in the 1980s prompted the National Marine Fisheries Service to list Snake River sockeye salmon as endangered under the Endangered Species Act, and a multi-agency effort was initiated in 1991 to prevent their extinction. The recovery effort focused on the development of a captive broodstock coupled with evaluation and enhancement of nursery lake habitats. Large populations of nonendemic kokanee salmon <em>O. nerka </em>and the oligotrophic conditions of these lakes raised concerns about overstocking sockeye salmon and causing the collapse of macrozooplankton populations. To minimize these risks and to improve sockeye salmon forage production, the Shoshone- Bannock Tribes initiated a 4-year nutrient enrichment program in Redfish Lake. Liquid fertilizer (20:1, N:P by wt) was added weekly during the growing season from 1995 to 1998 to the surface of Redfish Lake with Stanley Lake (unfertilized) acting as a control. During the fertilization of Redfish Lake, Secchi depth decreased by 13% and compensation depth by 24%, while increases were observed for surface chlorophyll <em>a </em>(106%) and primary production (117%). Uniformity of phytoplankton communities throughout the experiment indicated that the Redfish Lake food web was efficient (without major carbon sinks) and improved forage conditions for macrozooplankton. Total macrozooplankton biomass increased 31%, and <em>Daphnia </em>spp<em>. </em>biomass increased by 225%, simultaneous to a 26% increase in <em>O. nerka </em>density. Also, during fertilization, overwinter survival of supplemented sockeye salmon increased 192% in Redfish Lake. However, meteorological conditions were partly responsible for these changes. In unfertilized Stanley Lake, during the same time periods, Secchi depth declined 27%, and compensation depth was reduced by 28%; chlorophyll <em>a </em>increased 16%, primary production increased 14%, and zooplankton biomass was stable. These changes highlight the importance of climate (meteorological forcing) and the need for a control when attempting to identify impacts from lake fertilization. Disproportionately larger increases in Redfish Lake chlorophyll <em>a</em>, primary productivity, and zooplankton biomass relative to observed changes in Stanley Lake provide evidence for the efficacy of nutrient supplementation in Redfish Lake.

scholarly journals Electrophysiological Studies of the Antrum Muscle Fibers of the Guinea Pig Stomach

1970 ◽  
Vol 55 (1) ◽  
pp. 48-62 ◽  
Author(s):  
H. Kuriyama ◽  
T. Osa ◽  
H. Tasaki
Keyword(s):  
Slow Wave ◽  
Longitudinal Muscle ◽  
Muscle Fibers ◽  
Circular Muscle ◽  
Slow Waves ◽  
The Other ◽  
Spike Generation ◽  
High K ◽  
Electrophysiological Studies ◽  
Guinea Pig Stomach

The membrane potentials of single smooth muscle fibers of various regions of the stomach were measured, and do not differ from those measured in intestinal muscle. Spontaneous slow waves with superimposed spikes could be recorded from the longitudinal and circular muscle of the antrum. The development of tension was preceded by spikes but often tension appeared only when the slow waves were generated. Contracture in high K solution developed at a critical membrane potential of -42 mv. MnCl2 blocked the spike generation, then lowered the amplitude of the slow wave. On the other hand, withdrawal of Na+, or addition of atropine and tetrodotoxin inhibited the generation of most of the slow waves but a spike could still be elicited by electrical stimulation. Prostigmine enhanced and prolonged the slow wave; acetylcholine depolarized the membrane without change in the frequency of the slow waves. Chronaxie for the spike generation in the longitudinal muscle of the antrum was 30 msec and conduction velocity was 1.2 cm/sec. The time constant of the foot of the propagated spike was 28 msec. The space constants measured from the longitudinal and circular muscles of the antrum were 1.1 mm and 1.4 mm, respectively.

beta-Adrenergic blockade of prostaglandin E2- and D2-induced erythroid colony formation

1983 ◽  
Vol 245 (5) ◽  
pp. C322-C327 ◽  
Author(s):  
M. Belegu ◽  
B. Beckman ◽  
J. W. Fisher
Keyword(s):  
Bone Marrow ◽  
Arachidonic Acid ◽  
Normal Mouse ◽  
Mouse Bone Marrow ◽  
Adrenergic Blockade ◽  
Beta Adrenergic ◽  
Bone Marrow Cultures ◽  
Beta 2 ◽  
Adrenergic Blocking ◽  
Marrow Cultures

beta-Adrenergic receptors have been linked to the actions of beta-adrenergic agonists as well as that of other hormones on erythroid cells. In the present studies, arachidonic acid, the precursor for the endoperoxide intermediates for prostaglandins, was demonstrated to produce a significant increase in erythroid colony (CFU-E) formation in normal mouse bone marrow cultures. Meclofenamate, a cyclooxygenase inhibitor drug that inhibits prostaglandins synthesis, significantly inhibited the increase in CFU-E colony-forming cells produced by arachidonic acid, thus establishing that arachidonic acid was probably converted to some prostaglandin or prostaglandin metabolite in the bone marrow to trigger CFU-E. Prostaglandins E2 (PGE2) and D2 (PGD2), both of which have been demonstrated to be produced in the bone marrow, were found in the present studies to increase the number of CFU-E colonies in normal mouse bone marrow cultures. DL-Propranolol, a beta 1, beta 2-adrenergic blocking agent, and D-propranolol, a non-beta-blocking isomer with nonspecific membrane stabilizing effects, both produced a significant (P less than 0.01) inhibition of the effects of PGE2 or PGD2 on CFU-E in murine bone marrow cultures. Butoxamine, a somewhat selective beta 2-adrenergic antagonist drug, also produced a significant inhibition of the effects of PGE2 on CFU-E in murine marrow cultures. These results indicate that the effects of beta-adrenergic blocking agents on prostaglandin-stimulated CFU-E are due to their membrane-stabilizing action rather than specific beta-adrenergic blockade.

Effects of Adrenergic and Cholinergic Drugs on Splenic Inflow and Outflow Before and During Adrenergic Blockade

1957 ◽  
Vol 189 (3) ◽  
pp. 599-604 ◽  
Author(s):  
Kenneth Ottis ◽  
J. E. Davis ◽  
Harold D. Green
Keyword(s):  
Splenic Vein ◽  
Blocking Agent ◽  
Significant Degree ◽  
Adrenergic Blockade ◽  
Venous Outflow ◽  
Splenic Volume ◽  
Blood Flows ◽  
Vascular Bed ◽  
Arterial Inflow ◽  
Adrenergic Blocking

Blood flows (electromagnetic flowmeters) and lateral pressures were recorded simultaneously from the splenic artery and vein during intra-arterial injections of adrenergic substances and methacholine. These injections were repeated after progressively increasing doses of the adrenergic blocking agent phenoxybenzamine. Epinephrine and arterenol simultaneously reduced arterial inflow and increased venous outflow and splenic vein pressure, and reduced splenic volume. Isoproterenol and methacholine, and epinephrine and arterenol during partial adrenergic blockade, increased arterial inflow and venous outflow and pressure, and increased splenic volume. This is the only vascular bed so far studied in which any significant degree of reversal of arterenol arteriolar constriction has been noted.

scholarly journals All-or-None Contraction and Sodium Channels in a Subset of Circular Muscle Fibers of Squid Mantle

1996 ◽  
Vol 191 (3) ◽  
pp. 337-340 ◽  
Author(s):  
W. F. Gilly ◽  
T. Preuss ◽  
M. B. McFarlane
Keyword(s):  
Sodium Channels ◽  
Muscle Fibers ◽  
Circular Muscle
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