“Bothrops jararaca”的意思、由来-开放百科全书

The drugs known as angiotensin converting enzyme (ACE) inhibitors, used for the treatment of hypertension and some types of congestive heart failure, were developed from a peptide found in the venom of this species.

Description

This is a slender and terrestrial species that grows to a maximum total length of 160 cm (63 in), although the average total length is much less.^[3]

The head scalation includes 5-12 intersupraoculars that are weakly keeled, 7-9 supralabials (usually 8) of which the second is fused with the prelacunal to form a lacunolabial, and 9-13 sublabials (usually 10-12). Midbody, there are 20-27 rows of dorsal scales (usually 23-25). The ventrals number 170-216 (rarely 218) and the 51-71 subcaudals are mostly paired.^[3]

The color pattern is extremely variable, consisting of a dorsal ground color that may be tan, brown, gray, yellow, olive, or almost maroon. Midbody, this color is usually somewhat lighter than the head, anterior and posterior. The dorsal ground color is overlaid with a series of pale-edged, dark brown subtriangular or trapezoidal markings on either side of the body, the apices of which reach the vertebral line. These marking may be situated opposite each other, or partially or completely juxtaposed; most specimens have a pattern with all three variations. In juveniles, the tip of the tail is white.^[3]

The head has a prominent dark brown stripe that runs from behind the eye, on either side of the head, back to the angle of the mouth, usually touching the last three supralabials. Dorsally, this stripe is bordered by a distinct pale area. The tongue is black, and the iris is gold to greenish gold with slightly darker reticulations.^[3]

Common names

The English common name is jararaca. In Argentina, it is called yarará and yararaca perezosa. In Brazil, it is referred to as caissaca, jaraca, jaracá, jararaca, jararaca-do-rabo-branco, jararaca-do-campo, jararaca-do-cerrado, jararaca-dormideira, jararaca-dominhoca and malha-de-sapo. In Paraguay and Uruguay, it is also called yarará.^[3]

Geographic range

This snake is found in southern Brazil, northeastern Paraguay and northern Argentina (Misiones). The type locality is listed as "Lagoa d'Arara am Mucurí" (Brazil) by Wied-Neuwied in 1825.^[1] Occurs from near sea level to over 1,000 m altitude.^[3]

Habitat

The species prefers deciduous tropical forests and savanna country, as well as semitropical upland forests. It is said to favor open areas, such as farmland, with nearby vegetation cover.^[3]

Feeding

Reproduction

Females are ovoviviparous, and are believed to produce about 20 young at a time.

Venom

Potency

This species is often abundant within its range, where it is an important cause of snakebite.^[3] It is the best-known venomous snake in the wealthy and heavily populated areas of southeastern Brazil, where it was responsible for 52% (3,446 cases) of snakebites between 1902 and 1945, with a 0.7% fatality rate (25 deaths).^[6]

The average venom yield is {{convert|25|-|26|mg}} with a maximum of {{convert|300| mg}} of dried venom. The venom is quite toxic. In mice, the median lethal dose ({{LD50}}) is 1.2-1.3 mg/kg intravenous, 1.4 mg/kg intraperitoneal and 3.0 mg/kg subcutaneous. For humans, the LD₅₀ is estimated to be {{convert|210|mg}} subcutaneous.^[7]

Effects

Typical envenomation symptoms include local swelling, petechiae, bruising and blistering of the affected limb, spontaneous systemic bleeding of the gums and into the skin, subconjunctival hemorrhage and incoagulable blood. The systemic symptoms can potentially be fatal and may involve hemostatic disorders, intracranial hemorrhage, shock and renal failure.^[6]

Medical uses

The drugs known as angiotensin converting enzyme inhibitors (ACE inhibitors), which are used for the treatment of hypertension and some types of congestive heart failure, were developed from a peptide found in the venom of this species in 1965 by Brazilian scientist Sérgio Henrique Ferreira.^[8]

See also

References

1. ^¹{{ cite book | author1 = McDiarmid RW | authorlink2 = Jonathan A. Campbell | author2 = Campbell JA | author3 = Touré T | year = 1999 | title = Snake Species of the World: A Taxonomic and Geographic Reference | volume = 1 | publisher = Herpetologists' League | isbn = 1-893777-01-4 }}
2. ^{{ cite web | work = The Reptile Database | url = http://reptile-database.reptarium.cz/species?genus=Bothropoides&species=jararaca&search_param=%28%28taxon%3D%27Crotalinae%27%29%29 | title = Bothropoides jararaca (WIED, 1824) }}
3. ^¹²³⁴⁵⁶⁷⁸⁹{{ cite book | author = Campbell JA, Lamar WW | year = 2004 | title = The Venomous Reptiles of the Western Hemisphere | publisher = Comstock | isbn = 0-8014-4141-2 | lccn = 2003007834 }}
4. ^{{ cite book | author = U. S. Navy | year = 1991 | title = Poisonous Snakes of the World | publisher = US Govt.; Dover Publications | isbn = 0-486-26629-X }}
5. ^{{ITIS|id=634867|taxon=Bothrops jararaca|accessdate=21 January 2007}}
6. ^¹{{ cite book | author = Warrell DA | year = 2004 | chapter = Snakebites in Central and South America: Epidemiology, Clinical Features, and Clinical Management | editor = Campbell JA, Lamar WW | title = The Venomous Reptiles of the Western Hemisphere | publisher = Comstock | location = Ithaca | isbn = 0-8014-4141-2 | lccn = 2003007834 }}
7. ^{{ cite book | author = Brown JH | year = 1973 | title = Toxicology and Pharmacology of Venoms from Poisonous Snakes | location = Springfield, IL | publisher = Thomas | lccn = 73000229 | isbn = 0-398-02808-7 }}
8. ^{{cite journal | author = Ferreira SH | title = A bradykinin-potentiating factor (bpf) present in the venom of bothrops jararaca | journal = Br J Pharmacol Chemother | volume = 24 | issue = 1 | pages = 163–9 | date = February 1965 | pmid = 14302350 | pmc = 1704050 | doi = 10.1111/j.1476-5381.1965.tb02091.x | url = }}