在袋鼠冬眠器中模拟异热健身景观,使用身体组成的变化来模拟袋鼠冬眠
Tamara Abarzúa1, Isidora Camus1, Felipe Ortiz1
1Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile.
Oecologia
|October 5, 2023
概括
冬眠允许动物通过节约能量在恶劣条件下生存. 这项研究发现,冬眠期间储存脂肪更多,每日能源消耗较低的动物具有更高的健康状况,证明了对高效能源使用的选择.
科学领域:
- 生态学和进化生物学.
- 生理学和新陈代谢
背景情况:
- 冬眠是通过节能来应对环境挑战的关键适应.
- 在个人和人口层面上量化冬眠的适应性价值仍然具有挑战性.
- 了解冬眠期间的能量消耗和脂肪利用是评估健康状况的关键.
研究的目的:
- 用非侵入性方法评估自然群体中冬眠的适应性价值.
- 为了量化Dromiciops gliroides冬眠期间的能量节约和身体成分变化.
- 为了确定对冬眠期间的每日能量消耗和脂肪积累的选择压力.
主要方法:
- 利用定量磁共振 (qMR) 进行非侵入性身体组成分析 (脂肪和瘦肉质量).
- 在温带雨林中使用户外围来模拟自然的冬眠条件.
- 应用模型选择和表型选择分析以估计选择系数 (β, γ, ρ).
主要成果:
- 在冬眠的每日能量消耗上显著的负面方向选择 (DEEH) (βDEEH = -0.58 ± 0.09).
- 在脂肪积累上显著的正向选择 (βFAT = 0.34 ± 0.07).
- 在DEEH和脂肪积累之间的正相关选择 (ρDEEH×FAT = 0.24 ± 0.07),有利于高脂肪储存和低能量消耗的个体.
结论:
- 选择有利于那些在冬眠期间最大限度地增加先前的脂肪积累并最大限度地减少每日能源消耗的人.
- 非侵入性的身体成分分析与半自然的围相结合,有效地描述了冬眠健身景观.
- 这些发现与已知的哺乳动物冬眠代谢率全量计一致,验证了这一方法.
相关概念视频
01:26Thermoregulation
1.0K
The human body has a sophisticated thermoregulation system that employs negative feedback mechanisms to maintain an optimal core temperature. When the core temperature drops, peripheral and central thermoreceptors send signals to the hypothalamus, activating the heat-promoting center. This center triggers several responses aimed at increasing the core temperature. First, vasoconstriction reduces the flow of warm blood from internal organs to the skin so that the heat is not lost from the skin,...
1.0K
01:09Clearance Models: Physiological Models
76
Drug clearance is a critical pharmacokinetic process involving the irreversible removal of drugs from the body through various organs over a specified time period. Physiological models are indispensable in determining organ-specific clearance, defined by the proportion of the drug eliminated per unit of time from the organ's blood volume.
The organ's clearance rate depends on the blood flow to the organ and the extraction ratio (E). The extraction ratio describes the organ's...
The organ's clearance rate depends on the blood flow to the organ and the extraction ratio (E). The extraction ratio describes the organ's...
76
01:25Metabolic Rate
399
The human body is a powerhouse of energy, with every cell performing numerous functions that require energy. This energy production and consumption is measured by the metabolic rate, which quantifies the total heat generated by all the body's chemical reactions and mechanical work. This measurement helps to determine the rate of kilocalorie (kcal) consumption needed to fuel all ongoing activities.
The Basal Metabolic Rate (BMR) measures the energy expended at rest.
Several factors influence...
The Basal Metabolic Rate (BMR) measures the energy expended at rest.
Several factors influence...
399
00:51Energy Budgets
9.3K
Organisms must balance energy intake with the energy required for growth, maintenance and reproduction. These trade-offs result in a variety of survivorship and reproductive strategies, including semelparity and iteroparity. Semelparous species, like annual plants, have only one reproductive episode in their lifetimes and consequently have short lifespans. Iteroparous species, by contrast, have many reproductive events during their lifetimes but have relatively few offspring. These two...
9.3K
01:25Metabolic States of the Body: The Absorptive State
704
During the absorptive state, which lasts approximately four hours after a meal, the body absorbs nutrients from the gastrointestinal tract. The carbohydrates, proteins, and lipids we consume are broken down into monosaccharides, amino acids, and free fatty acids for absorption. While carbohydrates and proteins are absorbed as-is, lipids are absorbed in their broken-down forms and then re-esterified into triglycerides within enterocytes before being packaged into chylomicrons. These absorbed...
704
01:18Metabolic States of the Body: The Postabsorptive State
341
The postabsorptive state usually starts about four hours after a meal and lasts until the next meal is eaten. During this time, the digestive system stops absorbing nutrients, and the body uses stored energy reserves to maintain stable blood glucose levels.
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...
Initially, glycogen stored in the liver is broken down to release glucose into the bloodstream, while glycogen in the muscles is broken down to supply glucose for energy directly within the muscle cells. As glycogen stores diminish,...
341