scholarly journals Weight and Length in the River Lamprey

Nature ◽  
1962 ◽  
Vol 194 (4833) ◽  
pp. 1093-1093 ◽  
Author(s):  
LIS OLESEN LARSEN
Keyword(s):  
River Lamprey

Thermoadaptation Characteristics of European River Lamprey Lampetra fluviatilis Smolts

2019 ◽  
Vol 59 (5) ◽  
pp. 805-809 ◽  
Author(s):  
V. K. Golovanov ◽  
N. S. Nekrutov ◽  
A. O. Zvezdin ◽  
A. K. Smirnov ◽  
I. A. Tsimbalov
Keyword(s):  
Lampetra Fluviatilis ◽  
River Lamprey

K+ transport across the lamprey erythrocyte membrane: characteristics of a Ba(2+)- and amiloride-sensitive pathway

1991 ◽  
Vol 159 (1) ◽  
pp. 303-324 ◽  
Author(s):  
K. Kirk
Keyword(s):  
Membrane Potential ◽  
Erythrocyte Membrane ◽  
Inhibitory Effect ◽  
Extracellular Ph ◽  
Transport Pathway ◽  
Full Effect ◽  
River Lamprey ◽  
K Concentration ◽  
86Rb Influx ◽  
K Transport

The characteristics of K+ transport in erythrocytes from the river lamprey (Lampetra fluviatilis) were investigated using standard radioisotope flux techniques. The cells were shown to have a ouabain-sensitive transport pathway that carried 43K+ and 86Rb+ into the cell at similar rates. Most of the ouabain-resistant 43K+ and 86Rb+ influx was via a pathway that was insensitive to cotransport inhibitors and to the replacement of extracellular Cl- or Na+. This pathway showed a strong selectivity for 43K+ over 86Rb+. It was inhibited fully by Ba2+ (I50 approximately 2.8 mumol l-1), amiloride (I50 approximately 150 mumol l-1) and ethylisopropylamiloride (I50 approximately 3.3 mumol l-1) and less effectively by quinine and by the tetraethylammonium ion. Inhibition by Ba2+ took full effect within a few minutes whereas the full inhibitory effect of amiloride took more than 1 h to develop. Experiments with the membrane potential probe [14C]tetraphenylphosphonium ion gave results consistent with the lamprey erythrocyte membrane having a Ba(2+)-sensitive K+ conductance that was significantly greater than the membrane Na+ conductance and which gave rise to a marked dependence of the membrane potential on the extracellular K+ concentration. The rate constants for Ba(2+)-sensitive 43K+ and 86Rb+ influx decreased (proportionally) with increasing extracellular K+ concentration in a manner that was consistent with the transport being via a conductive pathway. The decrease was attributed to a depolarisation of the membrane (in response to the increasing extracellular K+ concentration) and a consequent decrease in the driving force for the conductive movement of 43K+ and 86Rb+ into the cells. Ba(2+)-sensitive 86Rb+ influx increased significantly with decreasing cell volume and with increasing intracellular pH (at a constant extracellular pH) but increased only slightly with increasing extracellular pH. The pathway operated normally in the complete absence of extracellular Ca2+ but its activity decreased in cells pretreated with ionomycin and EGTA; this suggests a role for intracellular Ca2+ in the operation of the pathway.

A Micropuncture Study of Kidney Function in the River Lamprey Lampetra Fluviatilis Adapted to Sea Water

1980 ◽  
Vol 88 (1) ◽  
pp. 239-248
Author(s):  
A. G. LOGAN ◽  
R. MORRIS ◽  
J. C. RANKIN
Keyword(s):  
Fresh Water ◽  
Kidney Function ◽  
Sea Water ◽  
Chloride Ions ◽  
Water Reabsorption ◽  
Plasma Electrolyte ◽  
River Lamprey ◽  
Micropuncture Study ◽  
Urine Composition ◽  
High Concentrations

Micropuncture techniques have been used to investigate kidney function in lampreys adapted to hyperosmotic media. Plasma electrolyte concentrations were maintained well below corresponding concentrations in the external environment. Urine composition was variable, but generally showed high concentrations of magnesium, sulphate and chloride ions. Lampreys in 50% sea water produced urine which was hypo or iso-osmotic to plasma, whereas those in 100% sea water produced hyperosmotic urine. Urine flow rate in 50% sea water was one tenth of that in fresh water, due to a reduction in filtration rate and an increase in water reabsorption by the kidney. As in fresh water, little if any filtered water was reabsorbed by the proximal segment. Almost 90% of filtered water was reabsorbed by the kidney of 100% sea water lampreys and most of this must have occurred in the distal and collecting segments.

Measurement of Single Nephron Filtration Rate in the Kidney of the River Lamprey, Lampetra Fluviatilis L

1978 ◽  
Vol 77 (1) ◽  
pp. 57-69 ◽  
Author(s):  
R. J. MORIARTY ◽  
A. G. LOGAN ◽  
J. C. RANKIN
Keyword(s):  
Filtration Rate ◽  
Gel Filtration ◽  
Reference Substance ◽  
Nephron Filtration Rate ◽  
River Lamprey ◽  
Peritubular Capillaries ◽  
Single Nephron Filtration Rate ◽  
Single Nephron ◽  
51Cr Edta ◽  
Renal Clearances

The reliability of [3H]inulin as a reference substance for the measurement of glomerular filtration rate (GFR) in river lampreys was investigated. Simultaneously measured renal clearances of [3H]inulin and [14C]-polyethylene glycol (PEG) were not significantly different. Recoveries of [3H]inulin in the urine following its injection into the proximal tubule and urinary duct averaged 83.5±4.0% (n = 14) and 93.0±4.6% (n = 9) respectively. No evidence was obtained to suggest penetration of the tubular wall by [3H]inulin following its introduction into peritubular capillaries. Gel-filtration of lamprey plasma and urine produced no signs of any significant degradation of the inulin to fructose. [3H]inulin recoveries, though significantly below 100% (P < 0.001), were considered adequate to justify its use after allowing for possible sources of error. A mean single nephron filtration rate (SNGFR) value of 7.02±0.27 nl/min (n = 89) was obtained from the kidneys of anaesthetized freshwater lampreys. [51Cr]EDTA was found to be totally unsuitable for the measurement of GFR in this species.

Comparative Analysis of Autoxidation of Haemoglobin

2001 ◽  
Vol 204 (11) ◽  
pp. 2029-2033
Author(s):  
Frank B. Jensen
Keyword(s):  
Temperature Sensitivity ◽  
Oxidation Rate ◽  
Protective Role ◽  
Yellowfin Tuna ◽  
Histidine Residue ◽  
River Lamprey ◽  
Different Temperatures ◽  
Lower Temperature ◽  
The Impact

SUMMARY Autoxidation of oxyhaemoglobin (oxyHb) to methaemoglobin was measured at different temperatures in haemoglobin solutions from Atlantic hagfish, river lamprey, common carp, yellowfin tuna and pig. The aims were to evaluate the impact of the absent distal histidine in hagfish haemoglobin, the importance of oxyHb being either monomeric (hagfish and lamprey) or tetrameric (carp, tuna and pig) and to gain information on the temperature-sensitivity of autoxidation. The rate of autoxidation was lower in hagfish than in carp, yellowfin tuna and lamprey haemoglobins at any given temperature. Substitution of the distal histidine residue (His E7) with glutamine in hagfish haemoglobin was therefore not associated with an accelerated autoxidation, as might be expected on the basis of the normal protective role of His E7. Glutamine may have similar qualities to histidine and be involved in the low susceptibility to autoxidation. The low oxidation rate of hagfish haemoglobin, together with an oxidation rate of lamprey haemoglobin that did not differ from that of carp and yellowfin tuna haemoglobins, also revealed that autoxidation was not accelerated in the monomeric oxyhaemoglobins. Pig haemoglobin was oxidised more slowly than fish haemoglobins, demonstrating that fish haemoglobins are more sensitive to autoxidation than mammalian haemoglobins. The rate of autoxidation of hagfish haemoglobin was, however, only significantly greater than that of pig haemoglobin at high temperatures. Autoxidation was accelerated by rising temperature in all haemoglobins. Arrhenius plots of carp and yellowfin tuna haemoglobin revealed a break at 25°C, reflecting a lower temperature-sensitivity between 5 and 25°C than between 25 and 40°C.

River lamprey present an unusual predation threat to Atlantic salmon smolts in Lough Neagh, Northern Ireland

2020 ◽  
Vol 97 (4) ◽  
pp. 1265-1267
Author(s):  
Richard J. Kennedy ◽  
Warren Campbell ◽  
Kevin Gallagher ◽  
Derek Evans
Keyword(s):  
Northern Ireland ◽  
Atlantic Salmon ◽  
Predation Threat ◽  
Lough Neagh ◽  
River Lamprey
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